Chris Christie Endorses Mitt Romney For President In 2012 GOP Primary [UPDATED]

Hanover, N.H. – New Jersey Gov. Chris Christie Tuesday endorsed Mitt Romney for the GOP presidential nomination, giving the primary front runner a head of steam heading into Tuesday night's debate.

"Mitt Romney is the man we need to lead America and we need him now," Christie said, standing alongside Romney at a press conference in nearby Lebanon, N.H.

Christie said it was Romney's experience in both business and government that had convinced him to endorse him.

"It's been really, in the end, an easy decision for me," Christie said.

Christie also took a veiled swipe at Texas Gov. Rick Perry, who entered the race later than most in August and has appeared overwhelmed at times during the campaign.

Romney, Christie said, "is not someone who just is deciding to run for president off the back of an envelope, who just wandered into it and said, 'Hey, this seems like a good idea, let's see how it goes.'"

"This is somebody who has thought and listened and planned for a good long period of time about what he would do if he was given the honor of being president of the United States," said Christie, who only a week ago publicly ended months of speculation about whether he would jump into the race late.

And Christie also defended Romney from attacks by Perry on the health care overhaul that Romney signed in 2006 for Massachusetts. The Perry campaign has ramped up attacks on the program as a model for President Obama's national health program, but Christie was forceful in rejecting that argument.

"We should not allow people, for political purposes, to try to be disingenuous about what Gov. Romney did, and compare that to what happened and what is happening with federal health care legislation supported by the president," Christie said.

Christie said it was "completely intellectually disingenuous" to compare Romney's plan to Obama's, arguing that Obama's overhaul includes tax increases and Romney's doesn't. He also said Romney was doing what he thought was best for his state, and that each state should be free to make their own decisions about how to address problems like rising health care costs.

"I am proud of him for standing up for doing what he believes was right. That may not be right for New Jersey, it may not be right for Montana, it may not be right for California. Those governors will make that decision," Christie said. "But do not try to equate what's happened in Obamacare with what Gov. Romney did in Massachusetts."

To top it all off, Christie backed Romney's denunciation of a Texas pastor who on Friday said evangelicals should back Perry because he is a "follower of the Lord Jesus Christ" and that Mormonism - Romney's faith - is "a cult."

Christie's support will help Romney solidify his standing as the candidate to beat, and may bring over to the former Massachusetts governor's side some of the money and support that has been on the sidelines in the Republican establishment.

"There are a lot of people that follow Chris Christie," Eric Holcomb, chairman of the Indiana State GOP and a top adviser to Gov. Mitch Daniels, told The Huffington Post.

Holcomb said he was "not surprised" by Christie's decision.

And Romney's courting of Christie began the day he announced that he wasn't running, with personal calls and the intercession of key donors. But Perry's mistakes and history also played a role in Christie's coming to a decision so quickly.

"Mitt talked to him immediately," said Tom Rath, a key Romney advisor. "First Christie had to get out, then we could go to work. There were two or three calls that first day."

Though Christie and Romney are an odd couple stylistically, there are links between them that likely helped facilitate the partnership. A key intermediary was New York Jets owner Woody Johnson, said Rath, along with other Christie fans who urged the governor to endorse Romney as the best answer to the country's economic problems. Johnson led a group of Christie donors who have moved en masse to Romney in the last two weeks. Many are based in New Jersey.

Another key to the endorsement was that Christie's media advisers Russ Schriefer and Stuart Stevens are also Romney's. According to Romney campaign counsel Ben Ginsberg, Schrieffer and Christie go back to 1999 when Christie was George W. Bush's campaign counsel in New Jersey and Schrieffer was a Bush field man in the state. Moreover, Christie's inner circle has largely been dominated by former advisers to Rudy Giuliani's 2008 campaign and Romney's 2008 New Jersey campaign. State Sen. Joe Kyrillos (R-Monmouth County), a former Republican state chairman and one of Christie's closest allies, chaired Romney's 2008 campaign in the Garden State. Kyrillos, who is considering a 2012 U.S. Senate race, was the chairman of Christie's 2009 campaign and swore Christie in as a Morris County freeholder in the 1990s.

Many New Jersey Republicans have been taking a back seat in the 2012 endorsement sweepstakes, waiting for Christie to signal his preference. Last year, U.S. Rep. Leonard Lance (R-N.J.) told a business group in Summit, N.J., that he was planning to wait for Christie's endorsement before he made his own, but indicated that he and other past Romney supporters would be encouraging Christie to back the former Massachusetts governor.

Yet a big part of the sales job was done by Perry, both through what he said and what he didn't, according to a source from a third camp who asked not to be identified so that he could speak freely. Christie was put off in particular by two things: Perry's ill-named rural hunting camp and by his silence on the comments of a Texas pastor who called Mormonism a cult. "Christie didn't like that stuff," this source said, "which made the Romney sales job a whole lot easier."

Romney acolytes are spinning the endorsement, coming a few hours before the next debate in New Hampshire, as a coup that will solidify their candidate's lead -- even though he trails "No Opinion" in the latest national polls.

"This is the start of the coming together," said Rath, standing outside the Hanover Inn with a broad smile on his face.

Having the combative Christie in his corner for tonight's debate is a start, but his backing may not win over grassroots conservatives, who have liked Christie’s blunt rhetorical style and his record in New Jersey, but may not see him as one of their own.

Meanwhile, Perry is reeling at the moment after stumbling in his first three debates and has fallen precipitously in the polls. Christie's decision to back Romney will increase the pressure on Perry to perform well Tuesday night.

Perry's campaign tried to shrug off the news. The Texan's top spokesman, Ray Sullivan, implied it was a case of regionalism.

"Northeast Republicans are sticking together in this case," Sullivan said on Fox News.

Howard Fineman reported from New Hampshire. Jon Ward reported from Washington. John Celock contributed to this article from Washington.