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Sen. John McCain endorses 'rising star' Mitt Romney

Photos by Brian Snyder / Reuters

Republican presidential candidate and former Massachusetts Governor Mitt Romney is joined by U.S. Senator John McCain at a campaign stop in Manchester, N.H. on Jan. 4, 2012, one day after Romney won the Iowa caucus.

Jonathan Ernst / Getty Images

From governor's son to presidential contender, a look at the life of Republican Mitt Romney.

The Associated Press reports that Mitt Romney accepted an endorsement from Arizona Sen. John McCain, the 2008 Republican presidential nominee, as he pushed for an overwhelming victory in next week's New Hampshire primary.

McCain, who is still hugely popular in the state, said his endorsement was intended to help Romney "get an overwhelming vote that will catapult this candidate to the White House."

McCain and Romney haven't always been political allies. McCain beat Romney in the 2008 New Hampshire primary, and there is a history of acrimony between the two. But Romney eventually endorsed McCain in 2008.

Cindy McCain, wife U.S. Senator John McCain, left, and Ann Romney, wife of Republican presidential candidate and former Massachusetts Governor Mitt Romney, arrive for a joint appearance of their husbands in Manchester.

John Makely / msnbc.com

Sen John McCain autographs a magazine cover for a fan following his endorsement of Mitt Romney at Central High School in Manchester, Wednesday, Jan. 4.

John Makely / msnbc.com

Brian Murphy with daughter Brianna, 3, brave the cold temperatures in downtown Manchester to get the word out about a Romney rally at Central High School on Wednesday.