Two Brave Endorsements for Rubio: Romney and Cantor

Now that Marco Rubio is a heavy favorite in Florida, the endorsements are rolling in.

De facto GOP White House favorite Mitt Romney endorsed Rubio yesterday, and, as Josh Green noted, Romney got beat up over this: it's easy to endorse Rubio now that he leads his Senate primary against Gov. Charlie Crist, the former frontrunner, by more than 20 percentage points. What about when Rubio was a mere conservative upstart, trailing Crist by 20 last fall--when his biggest backers were the influential blogger Erick Erickson and the free-enterprise DC interest group the Club for Growth?

This morning, another big-time Republican hopped on the Rubio train: House Minority Whip Eric Cantor.

In a statement posted to Rubio's campaign website, Cantor praised Rubio's platform to restrain government spending and said that "We are a nation at a crossroads, and we need responsible leadership in Washington. Marco Rubio is just the type of leader our country needs and will make an excellent Senator for the State of Florida. The Obama Administration is working hand-in-hand with Senate Leader Reid and House Speaker Pelosi to fundamentally change the America we know and love."

The tide has turned steadily in Rubio's favor since last year, and the race reached a tie in December. Since then, Rubio has opened up a commanding lead. Here's how polling in the race has gone, compiled and charted by the polling gurus at Pollster.com:

It's almost impossible to retain any support from fiscal-conservative activists and Tea Party groups without endorsing Rubio, and their passion for the candidate is so intense that it pressured the Republican establishment to respect him, even when it looked like he couldn't win.

Looking at the polls, it seems logical that Crist would disaffiliate from the GOP and run as an independent. Barring a massive swing between now and August, when the primary election will be held, it would be tough for Crist to defeat Rubio in the primary. But if he runs as an independent, a three-way race with Rep. Kendrick Meek (D) would be close:

The pendulum could always turn back in Crist's favor, but it looks like Rubio might be the only viable GOP-ticket candidate in the race. Who else, then, would top Republicans endorse?