I subscribe to the view that we're down to either Romney or Santorum (Perry is toast; Newt has self-immolated, though he has a long-shot chance in SC; does anyone really see a surge for Huntsman?; Paul will not be the nominee).
But, regardless of the nominee, there are some no-brainer potential running mates. Here's my list of the best:
Marco Rubio, FL Senator — excellent for Romney; probably OK for Santorum, but both are Catholics; from an important state; would help with Hispanics, though his family is from Cuba, not Mexico; not a lot of national experience
Pat Toomey, PA Senator — excellent for Romney; very important state; shores up the base for Romney; he's really smart and well-spoken--obviously a no-go with Santorum
Rob Portman, OH Senator — very smart with excellent credentials (director of Office of Management and Budget); from Ohio, another swing state--he could work for either candidate
Paul Ryan — great national voice for fiscal sanity; winning personality; helps win Wisconsin; I'd pay money to see him debate Biden: he works for either candidate
Susana Martinez, NM Governor — great help with Hispanics, but largely an unknown; would help with women voters
Nikki Haley, SC Governor — would help with Evangelicals, but like Martinez is a bit unknown; would help with women voters
Tim Pawlenty, former MN Governor — quit too soon; Evangelical (right?); solid but not exciting; would certainly help in Minnesota
Rick Santorum—might be a good match with Romney heading the ticket, but wouldn't Toomey help more in PA?
I'm sure I missed some (could Mitch Daniels be persuaded to take the second slot?) and would love to hear your comments (I hear Charlie Crist is available)?
Second topic: If he gets desperate, I can see Obama dumping Biden for Hilary. Would she do it? I don't see a lot of upside for her.