you probably remember the tense moment saturday when a man rushed donald trump. well today that man, thomas demassimo was charged with a federal crime, entering a secret service restricted area. now to the democrats, hillary clinton won at least four more states last night. she now has nearly 2/3 of the delegates she need for the nomination. here is nancy cordes. >> thank you, florida! thank you, north carolina! thank you ohio! >> clinton had more thanking to do than her own campaign had expected. she swept four states by as much as 31 points. a feat sanders did not acknowledge at his rally. >> next week, arizona has a very important election. we will win. >> reporter: in a statement the vermont senator insisted he is still on a path to win the nomination. and that the primary calendar favors us in the weeks and months to come. but, that's also what he said before last night's blowout. >> in a memo today, the clinton campaign laid out the odds against sanders. nearly half of the remaining pledge delegates are in just three states. california, new york, and pennsylvania. senator sanders would have to win them by 20 points. and rack up a string of victories just to pull even. in short they argued, clinton's delegate lead is nearly insurmountable. >> we are moving closer to securing the democratic party nomination and winning this election in november! >> the clinton camp knows there is a fine line between confidence and arrogance. they say they will not be calling on sanders to drop out but it is his decision. scott when she faced a similar choice in 2008, clinton stays in all the way to the end. >> nancy cordes, thanks. now with confidence and not a hint of arrogance we'll turn to john dickerson, our cbs news political director and anchor of "face the nation." >> trump lost a big one in ohio last night. how damaging was that? >> well not winning the 66 delegates mean trump has to do better in the future. before last night he had won 44% of the delegates now. he need to win 52% of the remaining delegates. up for grabs. but, rules in later contests give winners a greater share of the delegates. that will help him and there was evidence last night, particularly in florida, where he got 48% of the vote, that his results improve as the field shrinks. so he has shown capacity to do better in the future. >> now if republicans wanted to deny trump the nomination is there a way they could do that in the coming contests? >> they have to win enough delegates to deny him the majority of delegates. that means beating him outright in the state's where they are winner take all. he may be weaker, montana, nebraska, south dakota. in the states where he is strong. that distribute delegates proportional. they have to come in close second to shrink the delegate prize. that is going to be hard to do. kasich and cruz, keep splitting the nontrump vote. >> maurko rubio dropped out last night. the face of the new republican party. hispanic, young, what happened. >> he was selling the wrong product. that youth, that outreach expan tugs new voters and that optimism. it was a year when voters wanted a champion for their anger. and also, his greatest legislative achievement, pushing a comprehensive immigration reform bill, that's part of what had stirred up that voter anger in the first place. >> john dickerson, we'll be watching you sunday on "face the nation." john, thanks. today north korea sentenced a university of virginia student to 15 years of hard labor for what amounts to a college prank. otto warmbill. er arrested in january for stealing a propaganda banner while visiting with a tour group. the sentence came one day after president obama approved new sanctions against north korea for recent missile launch and nuclear test. the "cbs overnight news" will be right back. hey ladies, heard the good news? spray 'n wash is back... and even better. it's powerful formula removes everyday stains the first time. which is bad news for stains, and good news for you. spray 'n wash. back 'n better. (sound♪ of music ♪histling) introducing new k-y touch gel crème. for massage and intimacy. every touch, gently intensified. a little touch is all it takes. k-y touch. ♪ ♪ ♪ ♪ geico motorcycle, great rates for great rides. can this much love be cleanedrlin' by a little bit of dawn ultra? oh yeah. one bottle has the grease cleaning power of two bottles of this bargain brand. a drop of dawn and grease is gone. thousands of patients have been urged to get test ford hiv and hepatitis. after a hospital worker was charged with stealing pain medication. here is ben tracy. 28-year-old rocky allen was a surgical technologist at swedish medical center outside of denver. he was arrested last month on federal charges of stealing and tampering with syringes of fentanyl, a painkiller more powerful than morphine. court documents say allen removed syringes and replaced them with similar ones containing an undisclosed substance. because hospital officials don't know what allen may have done with replacement syringes, 3,000 former patients are being tested for possible exposure to hiv and hepatit hepatitis. attorneys say two people have tested positive for hepatitis-b. holland hoskins represents some patients. >> patients who had surgery at swedish medical center at the time period rocky allen was a surgical test. tested by labcorps and positive for blood born pathogens. 1,500 patients are tested in the seattle area where allen worked. allen banker is representing allen's potential victims. >> lying about his resume where he had been. know he had been fired for the same thing at facilities. >> allen has been fired at three homes in three different states. including, scripps green in la jolla. a spokesperson for the hospital. >> he was witnessed by a colleague attempting to divert medication, switching out a -- a -- a -- a syringe of, of fentanyl for saline. >> according to his termination letter, allen admitted swapping syringes and planned to inject the drug. rocky allen also served in afghanistan and was court martialed by the navy in 2011 for stealing the same drug. the records of that would have been available to an of these hospitals before they hired him. but, scott they either did not do a thorough enough background check or they ignored it. >> ben tracy in the l.a. newsroom. ben, thank you. we'll be right back. thunderstorms in are in the forecast in flood soaked southeast texas along the louisiana border. deweyville and orange seeing the worst floods in 130 years. hundreds of homes have been swamped. last month. virginia mcloren danced with the obamas, yesterday celebrated her 107th with the harlem globetrotters at the school where she volunteers. did tricks, magic circle, spun the ball wind auz given her own jersey. 107, of course. norma bowerschmidt is having a ball too. we will have her story next. ,, ,,,,,,,,,,,,,, we end with a lesson in living life to the fullest. every minute, every mile. here is david begnaud. >> were you ever a beach girl before this? >> no. >> reporter: the story of 90-year-old norma starts with an end of life decision. >> they wanted to operate and everything right away. i says, no. we'll just leave it be. >> reporter: it was uterine cancer. two days after that diagnosis, norma's husband of 67 years, leo, died. >> i know went up here some place. >> her son, tim and ramie, the family they had left. they live on the road in the rv. >> tim was you either come along with us or we have to put you in a nursing home. because i couldn't stay by myself. >> she just sat there quietly for a minute. i think i would like to come along. >> ready to roll. >> so began the road trip with the fab 4. tim, norma, raimie and ringo the dog. they left michigan and made it to rushmore. she saw the presidents. and then, old faithful at yellowstone. gazed into the grand canyon. looked down on florida from a hot air balloon. had her first pedicure in georgia and indulged in more beer and cake than she can remember. >> did you think you would have this much fun at 90? >> no. no. >> want to pop a wheely for him, mom? >> sure, why not. >> i have never seen her smile this much. >> tomorrow i will be teaching my kids about you. >> ramie posting about their trip on facebook. now more than 200,000 people are getting to know norma. >> you are a sensation. >> her own son is getting to know her too. >> this allowed me to have discussions i never thought i would have with my mom. to find out things you found out. she and my dad met. >> you didn't know your parents met at a bar until she told us? >> no. >> they have logged more than 7,000 miles so far. there is still a lot left on her to do list. >> that have given me a new lease on life i should say. >> you think you will live the rest of your life on the road. >> yes, i probably will. >> hi, norma. >> hi, norma. >> if you see her along the way, wave. because she will make you smile. david begnaud, cbs news, driving ms. norma in saint augustine, florida. >> that's the "cbs overnight news" for thursday. for some of you, the news continues. for others check back with us a little later for the morning news and cbs this morning. from the broadcast center in new york city, i'm scott pelley. welcome to the overnight news. i'm don dahler. after his big win in tuesday's primaries. gop front-runner donald trump apparently thinks talk is cheap. next week's planned republican debate has been canceled after trump announced he wouldn't attend. that got john kasich to bow out and left fox news with the prospect of ted cruz arguing with himself. so they called the whole thing off. the next voting comes tuesday with primaries in arizona and utah. and democratic caucus in idaho. for the gop, down to three candidates. marco rubio called it quits after he lost his home state of florida. major garrett reports. >> donald trump needs to win half of the remaining delegates to clinch the nomination. if not, trump and republican foes establishment and otherwise will have to fight it out at a contested convention. >> we are going to go forward. we are going to win. more importantly we are going to win for the country. >> donald trump celebrated big swing state victories tuesday night and paused to ponder the question that vexed his opponent. why attacks against him don't appear to stick. >> my numbers went up. i don't understand it. nobody understands it. my numbers went up. >> trump won florida handily, typically that saments a republican's hold on the nomination. not this year. >> i want to congratulate donald trump on his victory, big victory in florida. >> it did knock marco rubio out of the race. >> the politics of resentment against other people will not just leave us a fractured party. thae they will leave us a fractured nation. >> rubio won half the hispanic vote but lost to trump 20 points. >> tonight it is clear while we are on the right side this year, we will not be on the winning side. >> john kasich long ignored on the campaign trail secured a crucial win at home in ohio. >> i labored in obscurity so long. people counting me out. >> kasich's first win spoiled trump's bid for a perfect night. he vowed to campaign until the party's convention in cleveland. >> we have got one more trip around ohio this coming fall where we will beat hillary clinton and i will become the president of the united states. >> ted cruz finished second in illinois and north carolina with missouri too close to call. enough he said to claim incremental progress. >> tonight we continued to gain delegates and continue our march to 1237. >> cruz zeroed in on jilted rubio supporters. >> to those who supported marco, who worked so hard, we welcome you with open arms. >> trump comparatively mellow steered clear of the insults that have come to define his campaign. sounding more and more like his party's leader. >> i spoke with mitch mcconnell today. we had a great conversation. the fact is we have to bring our party together. >> for the democrats, hillary clinton has all but secured her spot on the november ballot with big primary wins tuesday. she beat bernie sanders by 13 points in ohio. and took florida by more than 30 points. nancy cordes reports. >> this was apparently clinton's most dominant night of the campaign so far. she shut sanders out nearly everywhere. and her campaign this morning, won't describe her lead as insurmountable. they do point out it is twice as large as president obama's ever was. in 2008. >> thank you florida. thank you, north carolina. thank you ohio. >> as clinton celebrated sanders didn't even mention his losses to a crowd. more than 7,000 in arizona. but, he made it clear, he plans to go on. >> phoenix, are you ready for a political revolution? according to cbs news exit poll results, voters in all five states said clinton would make a better commander-in-chief than sanders. and that her plans are more realistic. >> every candidate owes it to you to be clear and direct about what our plans will cost and how we are going to make them work. >> that's the difference between running for president and being president. [ cheers and applause ] >> reporter: the sweep was a huge relief for clinton who openly worried earlier in the day that voters were getting complacent. >> people think they know who is going to win. they think i am going to be the nominee. they may not be turning out. we can't afford that. >> the surprise loss in michigan may have given them the volt they needed. the wins in ohio and illinois will blunt sander's argument clinton's strength is largely confined to the south. >> 2 million more votes nationwide. >> she is now nearly 2/3 of the way to the democratic nomination. and had harsh word last night. >> there is great anger for the likely gop nominee who was just a few miles away at mar-a-lago. >> our commander-in-chief has to be able to defend our country, not embarrass it. >> gop front-runner donald trump is warning of riots around the republican national convention this summer if he is denied the nomination. trump now has more than half of the delegates he need to become the nominee. and he said he follows a couple votes short and the convention decides on some one else there could be trouble. julianna goldman reports now on how a convention becomes contested. >> contested convention for the republicans means delegates will vote and revote until a nominee gets the majority. the voting process is complicated, it can involve multiple ballots. from the start the rules are thrown out the window. >> well are going to go all the way to cleveland and secure the republican nomination. >> john kasich's big win in ohio denied donald trump a full victory lap. >> we are going to go forward. we are going to win. >> the race for delegates continues. as republicans face the increasing odds of a contested convention. >> it's not necessarily a bad thing. >> rnc chairman preidus says mate be too early to tell. >> candidates believe they have a pathway to getting to majority of delegates before cleveland. we will be ready for anything. >> reporter: sources tell cbs news officials in the rnc, donors as well as the candidates, john kasich and ted cruz. >> help is on the way. >> are already planning for the possibility. >> today the democratic party is the party of the american people. >> traditionally political parties have a clear nominee heading into their conventions. >> let me make one further pledge. >> i accept your nomination. >> i proudly accept your nomination. >> for the presidency of the united states. >> it is a minor civil case. >> donald. learn not to interrupt. >> the campaign defied the rules. at contested convention, delegates submit bal lots until some one wins a majority. there can be multiple round of voting. first round, delegates are bound by the results of their state's primaries and caucuses. once you get into additional rounds. delegates no longer have those obligations and could throw their support behind some one who never officially entered the race. campaigns will be working behind the scenes to shift delegate support. >> some times that means candidates are jockeying, you know for the months leading into the convention. >> the last time the republican party held a convention without a clear nominee was 1976. gerald ford beat out former governor ronald reagan on the first ballot to secure the nomination. >> truly in historic territory. >> political historian says an open convention brings with it the risk of creating a deeper divide within the republican party. >> it's hard for me to believe that trump supporters are just going to allow some kind of deal making to go on between everyone loves how they feel in dark clothes. and to keep those darks from fading... there's woolite darks. it's free of harsh ingredients, keeping dark clothes looking like new for 30 washes so your love for dark clothes will never fade. woolite darks. the strength test.. like leather, skin is stronger when it's hydrated. that's why dove men+care bodywash has a unique hydrating formula to leave skin healthier and stronger. i'm gonna take mucinex sinus-max. enough pressure in here for ya? too late, we're about to take off. these dissolve fast. they're new liquid gels. and you're coming with me... you realize i have gold status? mucinex sinus-max liquid gels. dissolves fast to unleash max strength medicine. let's end this. jill and kate use the same dishwasher. same detergent. but only jill ends up with wet, spotty glasses. kate adds finish jet-dry with five power actions that dry dishes and prevent spots and film, so all that's left is the shine. for better results, use finish jet-dry. president obama's nomination of merrick garland to fill a vacant seat set off a firestorm of controversy. senate republicans insist they won't hold hearings on the nomination much less give garland an up or down vote. the next term of the supreme court could face cases involving health care, immigration, climate rules, and gun rights. and it is the constitutional right to bear arms that has a lot of americans on both sides of the issue vowing to stand their ground. we have two reports on this. starting with anthony mason and the second amendment. >> at the heart of the debate over guns in america, is a single inscrutable sentence. the second amendment of the bill of rights. the wording itself is unusual. isn't it? >> it's unusual, it's short, it's clogged with commas. >> reporter: michael waldman heads bren noncenter for justice at new york university law school is author of a biography of the second amendment. >> the second amendment says, a well regulated militia, being necessary to the security of the free state, the right of the people to keep and bear arms, shall not be infringed. what does that mean? >> reporter: the most disputed clause in the constitution is the phrase about militias which were of great concern when the bill of rights was written in 1792. >> at the constitutional convention, in philadelphia, there was a -- very big controversy about how to al low ka military power. >> professor of constitutional law at george mason university, says the state's fear the new government would try to disarm the 13 state militias which required every white male over 16 to own a musket. >> they were very worried the states were deprived, would be deprived of their purr to resist federal tyranny. >> the militia is our safety. patrick henry argued. we can hatch no security without it. >> while guns were common place then. so were gun regulations. new york and boston, prohibited the firing of guns within city limits. and in the notes for the constitutional convention, waldman says. >> there is literally not a word about it protecting an individual right for gun ownership for self protection, hunting, or any of the other things we think about now. >> there is one side that believes -- that this -- amendment refers specifically and only to militias. >> well, i know people say that. but it just can't be true. if you look at what the words say. >> yeah. >> it says the right of the people to keep and bear arms. it does not say the right of the states. or the right of the militias. it says the right of the people. >> the debate over the second amendment came to a head here at the supreme court in 2008. in a case filed over the capital gun laws, called district of columbia vs. heller. in a 5-4 vote the court affirmed an individual's right to keep and bear arms. striking down d.c.'s ban on handguns in the home. the inherent right of self-defense, justice antonin scalia wrote in the majority opinion has been central to the second amendment right. but scalia added, the right is not unlimited. also, leaving room for gun regulation. >> is that a continuing gray area. >> it is absolutely a continuing gray area. absolutely a continuing gray area. >> another gray area. is how the court might rule on future second amendment issues. after the sudden death of judge scalia in february. >> so. you know. a lot depends on, on -- on -- who replaces justice scalia. >> most people who live in urban areas can't imagine why anyone would need a room full of rifles and handguns. for millions of americans who live in the wide open spaces firearms are a way of life. here's ted koppel. >> reporter: itch you have ever wondered where the deer and the antelope still roam, this is it. it is still a storybook west, you know to so many people. >> reporter: the big fellow, looks like he has been riding all his life and bears a striking resemblance to teddy roosevelt, that's bob modell. this is his moon crest ranch, a few miles outside of cody, wyoming. >> boys! >> those are some of bob's ranch hand getting ready to feed the horses. when they head up into the mountains they will be carrying rifles for, protection against wolves and coyotes or to put down a horse that's broken a leg. even down here, a couple of the men carry handguns. >> will you never know when you may need it. >> reporter: it is an enormous piece of land. modell owns 5,000 acres and then there is another 195,000 acres of public land surrounding his ranch. so you are sitting on roughly 200,000 acres of my land. >> i am. >> well you are welcome. i appreciate that. >> i would say to you -- i am a good steward. i use it for grazing my livestock. and -- i am also, a licensed big game outfitter. and -- you're lucky to have me, you know, watching after your land. >> you know when -- when people who don't hunt look around a place like this and when you see all of the head up on the wall, they say, what the hell is that guy talking about? conservation, they're killing them. >> hunters played an important role in conserving not only wildlife, but, our resources upon which the wildlife live. >> there is no getting around it. guns are big in wyoming. more guns per capita than any state in the country. as for the residents of park county, that's where cody is located, well, here's the sheriff, scott stewart. >> if they have guns in the home. low end will be four to five. high end is going to be anywhere from -- 100 to more. >> and how many people in those counties do not have guns? >> i would say that, a very minority. >> still when it comes to the rate of gun related murders, wyoming is below the national average. >> share stoouewart will tell y he is all right. a handful of deputies. >> some times, you have a deputy on one side of the county. get a call. 40 miles away. chances are he is not going to get there to intervene in any conflict that is maybe going on. >> what you are telling me is people need to be able to take care of themselves. >> absolutely. >> guns are wechb into the tapestry of all of the old wyoming families. that, of retired senator, allen simpson for example. >> how long have you simpsons been out here? >> great grandfather came to jackson in 1884. my grandmother lived to be 100. she was born in salt lake in, in 1874. two years before the custer battle. she always carried a derrigner in her -- purse. >> take a few shots. >> the senator's son. with his son. mack. they call him, big mack. does this sort of match what your dad did with you, i mean, what al did with you? >> absolutely, ted. >> what i am doing here with the boys is exactly what we did. >> there is a real effort to instill gun safety. >> people in other places don't understand how careful we are. how much we understand and how we learn from a young age. >> age 13. dillon ramero is a crack shot. an expensive sport. his father had him draft a contract outlining what he is prepared to do in order to keep shooting. >> keep a gpa, 3.95. not do any drugs or alcohol. ever, pretty much. and just stay out of trouble with the law. my teachers. respect him and my mom. >> dillon started shooting when he was 7. that's how old ella is now. but she and her dad bo allen have already been at this for a while. what is the first time you shot a gun? i think when i was 5. >> you are an old hand. doing this a long time. you like coming out shooting with your daddy? >> yeah. respect starts now. respect of life. respect of -- country. respect of game. everything starts now. that all starts. when they're impressionable. >> haley. haley, turn around so you can see the camera. i want to know one thing. did you have a good time. did you enjoy this? would you like to do it again? >> at this point, some gun control advocates in our major sit jeez may be shaking their heads in disbelief. folks out here though, couldn't care less. >> they don't give a [ bleep ] what people think about them back there. while they're killing each other every day more than they are out here. why do we have to listen to that? >> out on a pheasant shoot says collin simpson, says people and their guns get along just fine. >> a community event. a family event. the memories that i have, with my father and my brother and my two boys, and my wife and my, my, i mean you name it. those are wonderful memories. >> to a great extent our perspective on guns is shaped by where we live. on this cushion for generations. alright kiddos! everybody off the backpack, we made it to the ottoman. i like to watch them clean, but they'll never get me on the mattress! finally there's a disinfectant mist designed for sofas, mattresses and more. introducing new lysol max cover. its innovative cap has a 2x wider spray that kills 99.9% of bacteria. max cover is another great way to lysol that. >> important message for residents age 50 to 85. write down this number now. right now, people are receiving this free information kit for guaranteed acceptance life insurance with a rate lock through the colonial penn program. if you are on a fixed income, learn about affordable whole life insurance that guarantees your rate can never increase for any reason. if you did not receive your information, call this number now. your acceptance is guaranteed, with no health questions. stand by to learn more. >> i'm alex trebek, here to tell you about a popular life insurance plan with a rate lock that locks in your rate for life so it can never increase. did you get your free information kit? 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>> they're not sure what it is. but they think it my be part of an astro, navigational tool. for those who don't remember, de gama was the portuguese explorer the first to reach india by sailing east in the fierce race for the trade and exotic spices. about the same time, his competition, a guy called christopher columbus, went west. and happened to discover america. the ship sailed from lisbon in portugal around africa to india, a trade route established some years earlier. when he returned to lisbon, the ship, captained by his uncle made the way to an island off the southern coast of oman where it ran into a violent storm and was apparently dashed against the rocks. all souls on board were lost the fateful day in 1503. the ship's where abuts have remained a mystery for 500 years. but that silver coin, forged in 1499 helps date the wreckage. >> that is the "cbs overnight news" for this thursday. for some of you the news continues. for others. check back with us a little later for, the morning news, and cbs this morning. from the broadcast center in new york city, i'm don captioning funded by cbs it's thursday, march 17th, 2016. this is the "cbs morning news." supreme court showdown. president obama introduces his nominee to replace antonin scalia but senate republicans vow he'll never make it to the high court. ducking the debate. donald trump says he won't attend the next scheduled showdown and fox news ends up pulling the plug. kicking off the future. taking a cue from hollywood, nike unveils self-lacing sneakers. a big league ballplayer chooses family over fortune and