That’s what Flip’s asking. He cites exit polling that shows that 17 percent of those voting in the Republican primary were independents and 3 percent were Democrats (emphasis added):

If I’m reading the poll correctly, it suggests 17% of Republican primary voters identified themselves as having no major party affiliation, while 3% identified themselves as registered Democrats.

One of the features of the Florida primary that was supposed to distinguish it from the other contests to date was that it was a closed primary, meaning only party-registered voters could vote in their respective primaries. This was one of those alluring intangibles that hinted at a Romney advantage relative to the earlier open primaries.

And indeed, the exit polling suggests that Romney likely matched McCain among Republicans in Florida (rounded to the nearest percentage point). From where I’m sitting, it appears Mitt Romney might’ve won the Florida primary.

Again, Florida has some ‘splainin’ to do.

UPDATE: Mom4Mitt points out in comments below that there is an indication that Florida poll workers were allowing independents to vote in a primary that supposedly required them to choose a party ballot. I guess that explains how McCain got so many “independent” votes.