2016 Likely Scenario:
Fmr. Sec. of State Hillary Clinton of New York/Sen. Sherrod Brown of Ohio - 375 EVs (56.8%)Sen. Rand Paul of Kentucky/Sen. Mike Lee of Utah - 163 EVs(41.3%)Although Christie is going to be the underdog that the people want to win the 2016 GOP primary, 2012 gave good light that the Republican field will be filled with nobody but Tea Party idiots again in 2016 and while I think Christie could possibly win the popular, Paul will get the delegates for the nomination. It would be no surprise either then that he would pick one of the other 3 Stooges (Lee or Cruz), but simply because Cruz is starting to actually become an enemy of the Tea Party, Paul might be convinced to pick Lee instead.
Hillary I imagine then would pick someone who's of the opposite sex, is a fierce liberal like her, and is especially from a big, swing state. It could end up being Mark Warner, Michael Bennet, or his name has never mentioned for the job, but if he wins the Governorship in 2014, Ed FitzGerald could even be a better nominee than Brown to bring those young voters out.