reporter: kimball brace has one of those computer programs. this is showing you a concentration of where the trump vote was being cast. reporter: he s hired by states across the country to draw their maps and showed us just how advanced the technology is now. by the time you get down to the census bloc level, you can end up getting exact populations for any given piece of geography. reporter: to be sure gerrymandering is happening in state houses all across the country, including those with democrats in charge. maryland republican delegate kathy shulaga. this makes no sense. look at this district that wraps around there. reporter: she s advocating a nonpartisan approach. this is the citizens redistricting commission, a nonpartisan commission. a fifth grader can look at these two maps next to each other and