John McCain endorses Mitt Romney

Arizona Sen. John McCain endorsed Republican presidential candidate Mitt Romney in New Hampshire today, the Associated Press reported. McCain was the Republican presidential nominee in 2008.

Romney, who is in New Hampshire to campaign in the state before next week's primary, was joined on stage by McCain, when he accepted the endorsement. 

"The time has arrived for Republicans to choose a presidential nominee; a new standard bearer who has the ability and determination to defeat President Obama and the strongest commitment to returning America to prosperity and defending our interests and values overseas," said McCain while announcing his support, the Chicago Sun Times reported. "I'm pleased to have made my choice, and to endorse Governor Mitt Romney for the Republican nomination for President."

Romney, the former governor of Massachusetts, has a strong lead in New Hampshire in the most current polls. McCain also remains popular in New Hampshire, where he won the primary in 2000 and 2008. 

The New York Times reported that choosing between Romney or Rick Santorum, a former Senate colleague of McCain's, was like picking between two old enemies.

McCain had a "prickly relationship" with Romney during the 2008 campaign, during which he accused Romney of supporting a "timetable for the withdrawal of troops from Iraq." Romney in turn accused McCain of the "kind of dirty tricks that I think Ronald Reagan would have found to reprehensible."

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