Totally fair to ask the candidates for their best argument for their own electability.
Romney's closing was strong and effective. He didn't hit the ball out of the park in this debate, but he did a solid job and he did nothing to stop the momentum which does seem to be headed back his way. He did a good job rebutting Gingrich's attacks.
Gingrich didn't do what he needed to do to clinch Florida. He didn't get a "big moment" like he did in the South Carolina debate, and he had some truly awful moments -- like whining about negative campaigning and calling for a truce. With no more debates for a month, he's in for a long haul, especially if discussion tomorrow turns a the controversy about whether he called Spanish a gutter language. His attempt to attack Wolf Blitzer looked contrived and cynical, and especially ineffective since Santorum beat him to the punch.
Santorum did a great job. Amazing, as I've said, that the anti-Romneyites aren't flocking around him rather than a divisive, flawed guy like Newt. Yes, some of his social stances might be controversial in a general election -- but this isn't really a year when voters are likely focusing on social issues.
Santorum won the debate -- but since Gingrich had a relatively weak night, that means Romney pretty much wins overall.