He's already said he won't be her running mate because he's running for president, not vice president.
And like Claudia said, the 25 and under vote is pretty low. Most of the people who vote are middle age to elderly conservatives, so the chances of Hilary or Obama winning are pretty slim. Also, in the history of the US the presidencies generally go in eras. IE, 3 or 4 republican presidents in a row, and then it switches to a democrat for 3 or 4 terms, and then back, etc. So as far as that it seems pretty likely that it will still be a republican, but it could always change.
I'm not going to say my position because I don't want to get into it with anybody.