Why endorse Romney now?

Last night Senator Marco Rubio, Republican of Florida, endorsed Mitt Romney for President. This endorsement came on the heels of an announcement that George H.W. Bush (the Elder) is going to endorse Romney as well.

Now that Romney has all but clinched the Republican nomination, what is the value of endorsing him now? To convince him that you were with him all along?

Governor Chris Christie of New Jersey endorsed him back when the outcome was still uncertain, when to do so was to risk being excluded from a possible Gingrich or Santorum administration.

But now? What's the point?

Rubio of course has had great incentive to wait and then go with the winner, as his is the name most often mentioned as a Vice Presidential pick. But for the other latecomers, backing Romney seems to show a certain lack of courage. And a certain pointlessness.

In the same spirit, I hereby boldly predict that Barack Obama will win the Presidency in 2008.