Honestly, neither one will take a VP slot...
Obama wins the nomination, he has to KNOW what happens to folks who get in the way of the Clintons' political aspirations.
Hillary wins the nomination, she has to know that many black radicals would be hoping to see her with crosshairs.
Each one is a danger to the other as a VP.
What kind of skeleton would work? 'Bout the only thing I can think of would be something major enough to cause felony charges NOW (a current crime, that a DA can go after)...