Which of the three remaining candidates would be most able to withdraw troops from Iraq? I didn't say most likely, I said most able. To my mind, the answer is John McCain. When he says the war is done, it will be. If he decides we have done all we can, he will be able to muster a majority to get out. Would he ever do such a thing? Probably not. But Jon Chait reminds us that McCain's neocon credentials are of relatively new vintage and coincided suspiciously with his own personal career needs:

McCain originally opposed intervention in Bosnia and worried about a bloody ground campaign before the first Gulf war (see "Neo-McCain," October 16, 2006). McCain's advisers include not only neoconservatives but also the likes of Henry Kissinger and Brent Scowcroft. It would hardly be unimaginable for McCain to revert to his old realism, especially if Iraq continues to fail at political reconciliation. He could easily be the president who ends the war.

I agree. Especially if the military leadership persuades him the alternative could be the destruction of US global readiness. Of the three leading candidates, I think Clinton has the least chance of withdrawing. She's too weak and polarizing to bring the country together on the matter, and too afraid to do anything that could be used, however unfairly, to taint the Democrats as weak on security. Her promise to end the war is about a bankable as her husband's promise to end the gay ban.