Veep Peep

Assuming it's not going to be Hillary, my nickel bet is on Barbara Boxer. That choice would help in a remarkable number of demographics. If you want to play the game, here is the list of current U.S. Senators and here's a page to find all the governors. Of course there are those not currently in office (e.g., Sam Nunn) or who hold other office (e.g., Mayor Bloomberg) so the potential pool is quite large. Have fun!