Kornacki expects Florida would be in contention:
[T]he Florida polling that now shows Romney crushing Gingrich would tighten dramatically. (Remember that in early December, when he was surging everywhere, Gingrich was the one with a commanding Florida lead; that’s how volatile these numbers can be.) This would set up a frantic ten-day campaign in Florida (which votes on January 31) that the media would likely portray as a referendum on Romney’s viability. There would probably be, as John Heilemann suggested on MSNBC earlier today, talk of party leaders lining up a consensus back-up candidate in the event of a second straight Romney loss (because Newt would still not be an acceptable option for most of them).
Bernstein wonders whether Santorum will drop out after South Carolina.
The Dish 