John McCain has won Florida. As a result, Rudy Giuliani apparently dropping out to endorse him (hurray!). Though Mike Huckabee seems to be staying in the race, it should become something of a two-man showdown between Mitt Romney and McCain heading into Super Tuesday.

Under these circumstances, we would tend to expect conservative elites and the activist base to coalesce around Romney, the more conservative candidate, and beat McCain in closed GOP primaries, as a Talking Points Memo reader suggests. I predicted (perhaps foolishly) back in 2005 that the conservative establishment would block a McCain nomination in the same way it did back in 2000.

However, as Charlie Cook points out, McCain is widely (and probably correctly) seen as the party’s best hope of preventing a Clinton or Obama presidency, which may be why he’s getting strong support from Republican elected officials. Also, the contempt for Mitt Romney among conservative elites seems to run pretty deep and McCain will get fawning media coverage for the next week.

But there’s an additional factor that could hurt Romney’s chances which no one is talking about yet. For him to beat McCain, he needs conservatives who were backing Huckabee to switch over and vote strategically for him as the best alternative to McCain. But many of Huckabee’s supporters are evangelical Christians who may not be comfortable with Romney’s Mormon beliefs. Will they make the switch? It’s not clear.

Update 1/30 9:15 AM: Via Ross Douthat, exit poll data from Florida shows that “49% of those who voted for Rudy today picked Mitt Romney as their 2nd choice while 44% picked McCain” while “those who voted for Huckabee overwhelmingly picked McCain as their top 2nd choice over Mitt Romney, 54% to 32%.” I’m puzzled about what’s going on, but this is certainly not good news for Romney.