Michael Brendan Dougherty thinks that Rubio is being underestimated as a presidential candidate:

But Rubio has charisma, at least the sort that works in American politics. He’s an impressive campaigner. And he can give a good speech. Even in a crowded GOP field, Rubio could be a formidable candidate.

Dougherty is right that Rubio’s immigration foibles alone are not reason enough to dismiss his chances. If support for some form of immigration amnesty disqualified Republican candidates from receiving the nomination, neither George W. Bush or John McCain would have ever been GOP standard-bearers. The bigger problem that Rubio has on that issue is that he is closely identified with endorsing part of Obama’s agenda, and apart from the debacle over the Senate immigration bill one would be hard-pressed to think of anything that he has done in the Senate except to call for more foreign wars, attack diplomacy with Iran, and defend a bankrupt Cuba policy.

Rubio has gone out of his way to give himself McCain’s political profile (i.e., pro-immigration, comically hard-line on foreign policy) without the rest of McCain’s biography, and in a party that is relatively more conservative than it was seven years ago that is a terrible place to be. Yes, McCain won the nomination in 2008, but that was after he had run against Bush and after he had served in the Senate for decades. A Rubio campaign now would be far more quixotic than McCain’s 2000 run. There are already a number of other better-funded, better-known candidates that fill the space that he would occupy as a candidate, and it is very difficult to see what Rubio offers–apart from delivering speeches well–that the other likely candidates don’t. In a less crowded, very different field of candidates, maybe Rubio would be formidable. In this cycle, he is more likely to be a distant also-ran, and if he’s not careful he’ll end up being a footnote.

P.S. When recalling McCain’s presidential campaigns, we shouldn’t forget the extremely friendly media coverage he received in 2000 and the generally positive coverage he got prior to winning the nomination in 2008. Rubio won’t have anything comparable to that.