John McCain endorses Mitt Romney, his bitter rival from four years ago

MANCHESTER, New Hampshire--Four years ago, John McCain and Mitt Romney could barely conceal their disdain for each other. Their rivalry for the 2008 Republican presidential nomination extended well beyond the usual competiveness between opposing campaigns, as their bitterness and personal dislike of the other man became overwhelmingly obvious every time the two candidates shared a stage.

When Romney eventually dropped his bid and endorsed McCain as the eventual nominee, the Arizona senator barely smiled or made eye contact with the former Massachusetts governor. The air was so thick with tension that even aides to the two men were caught off guard.

While McCain and Rommey never became close friends, their relationship has gradually become less chilly over the years—enough so that McCain backed off his pledge to stay neutral in this year's Republican presidential race and endorsed Romney on Wednesday.

There was still some awkwardness. Making their entrance to Kenny Loggins' "Danger Zone"--a mainstay of the McCain '08 soundtrack--Romney waved as McCain threw several thumbs up to supporters. At one point, McCain gave Romney a half man-hug and then stood idly by for nearly eight minutes as Romney gave an abbreviated version of his stump speech.

When he finally spoke, McCain said he was endorsing Romney because he was the best candidate in the race.

"I hope that we will get an overwhelming vote that will catapult this candidate to the White House," he said.

McCain's endorsement was no doubt timed at bolstering Romney's appeal in New Hampshire, a state McCain carried in the 2000 and 2008 Republican primaries but also a state where Romney doesn't need much help. Romney holds a commanding 27-point lead over Ron Paul in the state, according to a Suffolk University daily tracking poll.

But McCain's endorsement could also play well in South Carolina, a state McCain won in 2008 and votes on Jan. 21, right after New Hampshire. McCain is scheduled to travel with Romney to South Carolina on Thursday and Friday.

Perhaps the most notable thing about McCain's endorsement wasn't that he backed Romney but rather that he snubbed Jon Huntsman. The former Utah governor was one of McCain's earliest backers in 2008 and has largely modeled his 2012 bid off McCain's '08 operation.

Many of Huntsman's staffers previously worked for McCain, including his top strategist John Weaver.

On Wednesday, Huntsman downplayed the McCain endorsement.

"People are looking for a new generation of leadership," Huntsman said, according to a Twitter message posted by his spokesman Tim Miller. "You can get all the Doles and McCains in the world, but in the end nobody cares."

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