Morning update:
Gingrich apparently refused to call Romney to offer his concession. U MAD, NEWT?
Here's the exit poll crosstabs. In short, Mitt brings all the hot mamis to the booth. Really though, he dominated almost every category--even the youth vote, which is a big difference from the previous three contests.
This is perhaps a bigger loss for Santorum and Paul than it is for Gingrich. Ron Paul underperformed his poll standing, and lost the youth vote to Romney. Santorum was a second fiddle to Gingrich even among abortion single-issue voters, archconservatives and evangelical born-agains.
It'll be interesting to see if Florida has much effect on the next two contests (Maine and Nevada) because there's so little time for the campaigns to filth up the airwaves. Then a few days after that, we get Minnesota, Colorado and Missouri's not-a-real-primary popularity poll.
Then there's an unholy three-week gap before the next primary. I think that three-week gap is when you'll see Santorum and Paul drop out, and any third-party contenders to throw their hat in.
There are rumblings that The Donald is thinking of making a 3rd party run. Guess he wants to try and play his...
Trump Card.
EDIT: Oh, and in response to my earlier wondering about the Hispanic and Jewish votes:
Jewish voters were only about 1% of exit poll respondents and had no seection preference recorded.
Hispanics went overwhelmingly for Romney, but it should be noted that the Florida Hispanic population is disproportionately Cuban-American. The Cuban exiles are an altogether different political beast than various Central and South American enclaves elsewhere in the US.