Put Hillary Clinton in the search for a running mate . Mr. Singer it has gotten to the point where Hillary Clinton can focus on the remake and move past the primary season, but it is also clear that she needs to be thinking about how to incorporate Bernie Sanders movement and followers into her campaign. One of the questions would be, well, if you you pick a Vice President ial candidate who is to Hillary Clintons left . Who is from the Bernie Sanders wing of the party . That is one option available to her. And there are a few candidates who might scratch that itch. 40 sanders wing for the sanders wing of the party. Whether it is elizabeth warren, sherry brown from ohio, very popular amongst progressives. She has some real choices and some options that would be a way to tilt to that wing of the party and welcome them in. Steve massachusetts and ohio both have republican governors. So they will appoint a successor, even an interim successor, who will be a republican. How does that complicate what senator reid said earlier this year . Mr. Singer that is the question. You have a multilevel chess that goes on when you want to pick the running mate. Maybe someone who would help Hillary Clinton win ohio. Which is critical to win the white house. But the Ohio Governor it might thrwart the ability of the democrats to retake the majority in the senate. So it is a very complicated set of mathematics. Ried has said is not a problem. Frankly, the democrats believe that with donald trump on the ticket, particularly over the week or two, they have a have a good chance to take back the majority in the senate and losing one of those would not be a critical loss. Steve as you look at the demographics, where is Hillary Clinton weakest . How does she shore up in those areas . Mr. Singer it depends on how you ask the question and who you ask it of. The young people, someone who appeals to them. The minority populations, which have been very important for in the primaries, she was extraordinarily successful with latino voters and she might get a lot of voters from them to have a black or latino running mate. So maybe you pick someone like cory booker new jersey. And him you have the advantage of an africanamerican who is a young guy. Very energetic. He basically owns social media by himself. He has a terrific outreach that way. Maybe you pick someone like the congressman who is latino from california. Again, youth and energy, which would contrast with the fact that Hillary Clinton would be one of the oldest politicians ever elected again, this is the mass. Which of these things are most important to you when you choose a running mate . Steve two secretary members have been mentioned. Julian castro, we will hear from him in just a moment and also labor secretary perez. He has not been elected to anything. He is from the baltimore area. Very popular. What are their chances. Mr. Singer he is popular with the labor movement. That might be a choice to recognize the demographics with the national campaign. Castro, very young, hispanic, a lot of energy, a very charismatic person but he does not have a great deal of background in government. He is a young guy, basically. It might be hard to imagine him being president , which of course is an important thing. The guy who gets mentioned most is tim kaine, the senator and former governor from virginia. Tim kaine, maybe he helps you bring virginia, an important state for Hillary Clinton and also brings you the white male vote that Hillary Clinton needs to win and a sense of gravitas. That this guy can be the next president of the united states. There is always the issue that you want to be able to say, i am ready for this candidate to replace me in a moment of crisis if necessary. That is one of the great knocks against sarah palin. America was not ready to see her as president. Steve a longterm friend of the clintons come is it safe to assume he would be among those advising her, and who else is talking to her . Mr. Singer she is talking to everybody. We know she is in communication with Bernie Sanders for a conversation about what he wants and what his people want to see. We know that she is in deep conversation with senior democrats across the party. About starting to make a plan for what will happen next in the convention. Remember, the convention is partially an unveiling of your Vice President ial candidate. Building the narrative around your Vice President ial candidate, building the narrative narrative around Hillary Clinton as well. I suspect that she is getting input from everywhere. Oh, pick our candidate, pick our candidate. Several groups reached out and said hello, remember. Steve i will not ask you who you think she will pick, but when . Do you think it will be after the Republican Convention . What do you think are timeline is. Mr. Singer my suspicion is it will be after. But there are only a couple of days between. So you would have to move fast. But normally, you want to get a good roll out and a good balance for it. You wouldnt want to do it the day before the Republican Convention because it your message would get garbled with theirs. My suspicion is that it will be just before the democratic convention. But it is possible to move it back and do it before the convention begins. Holsinger, thank you for your time. Announcer now, and american profile with one of those mentioned as a possible Vice President ial nomination for every clinton. We talked with Julian Castro about his life and career. This is 35 minutes. Steve secretary castro, thank you for being with us. What is it like to grow up with an identical twin brother . Sec. Castro i like to think of it as a blessing and a curse. 99 blessing, 1 curse. My brother watch dean joaquin and i, to this day, are very close. And growing up, it was like having your best friend there the entire time. He and i shared bunkbeds growing up