Some interesting exit poll results for the Florida GOP primary in no particular order:
McCain relied on independent voters (or "independent voters"? UPDATE: see here and here) to put him over the top; he split Republicans with Romney 33-33.
Only 29% of Florida GOP voters support a "path to citizenship" for the "undocumented"; 46% of that 29% went to McCain.
Romney won a plurality of those voters who believed that either illegal immigration or terrorism was the most important issue of the election. McCain won a plurality of those voters who believed that either Iraq or the economy was the the most important issue. The economy is important to those who voted in the GOP primary: 45% of voters said it was the top issue.
The Crist endorsement seems important; a significant percentage of voters said it was influential.
On the age question, Romney won a plurality of voters age 25-39 and 50-64; McCain won those in their 40's and those 65+.