As to the person I think it will be (not my choice, but my guess), I’ve ranked them in four categories, and from most likely to least likely within each group:
Top tier, the finalists (1-4): Marco Rubio, Bob McDonnell, Paul Ryan, Rob Portman
Second tier, possible (5-8): Tim Pawlenty, Susana Martinez, Kelly Ayotte, John Thune
Third tier, not likely (9-10): Chris Christie, Bobby Jindal
Shed a tear, no chance: Rick Santorum, Newt Gingrich, Sarah Palin, Condoleezza Rice, Michele Bachmann, Allen West, Herman Cain
In honor of tomorrow, I'd move the Fat Man from the third to the first tier.