Former Massachusetts Gov. Mitt Romney (Gage Skidmore, Creative Commons)

"Of all the candidates, Mitt Romney possesses the strongest vision for America's leadership role in the world, and I am proud to endorse him," Bolton said, according to a statement released by Romney’s campaign Thursday. "President Obama has sapped America's credibility abroad, weakened our military and failed to lead on issues vital to U.S. national security... Mitt Romney will restore our military, repair relations with our closest allies, and ensure that no adversary—including Iran— ever questions American resolve."

Bolton was the U.S. ambassador to the United Nations under President George W. Bush.

In a statement Romney welcomed Bolton’s support and said he looks forward to "consulting with him" during the campaign.

"John has been a staunch defender of U.S. interests and values, both while he was in and out of government," said Romney.

Former Massachusetts Gov. Mitt Romney has been touted as the candidate most likely to become the Republican candidate for the 2012 election. 

Earlier this week Romney's campaign announced it has raised "more than $56 million so far in the primary," with $24 million raised in the fourth quarter.

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