New Jersey Gov. Chris Christie endorsed former Massachusetts governor Mitt Romney in New Hampshire today, providing the frontrunner for the GOP presidential nomination with a boost on the verge of tonight’s New Hampshire debate.

New Jersey Gov. Chris Christie announces that he will not run for president in 2012, Tuesday, Oct. 4, 2011, at the Statehouse in Trenton, N.J. (AP Photo/Mel Evans)

“Americans cannot survive another four years of Barack Obama,” said Christie. “Mitt Romney is the man we need to lead America.” Christie added that Romney represents the “best of both worlds” given his experience in the private and public sector.

Christie said that Romney’s detailed economic plan, his willingness to stand by his health care plan and the fact that he is the best chance for Republicans to win the presidency.

For his part, Romney called Christie a “real hero”.

Christie and Romney will take part in a tele-townhall today at 5 pm; the Romney campaign says 750,000 voters from 20 states including Iowa and New Hampshire.

Back in May, Christie praised Romney for his speech defending and explaining his Massachusetts health care law. “That type of candor is what Americans expect from a serious presidential candidate today,” Christie said at the time.

Sources close to the process said that Romney’s courtship of Christie was a long one but refused to get into details. Christie is expected to address those matters at his press event announcing the endorsement.

Christie’s backing should provide a major boost to Romney who has been making the case for weeks that he is the best — and perhaps only — candidate who can beat President Obama in 2012.

Christie, a favorite of tea party and establishment types alike, has emphasized the need for the GOP to nominate someone not who they agree with on every issue but rather someone who can win.

He ruled out a presidential bid less than two weeks ago, arguing that his heart was still in New Jersey and that the time was not right for him to run.