Jon Huntsman Jr. will make his official announcement on Monday (Creative Commons).

Huntsman's announcement comes on the coattails of a disappointing third place finish in the New Hampshire primary, where he had campaigned extensively. Huntsman was also polling poorly in South Carolina, which will hold the next Republican presidential primary on Saturday.

According to a POLITICO source, Huntsman’s rationale for backing Romney after he had lambasted him for weeks during the primary is that he does not want to block the person best prepared in the field to beat President Barack Obama.

Tim Miller, a spokesman for the Huntsman campaign, told the AFP that Huntsman was "proud of the race that he ran" but "did not want to stand in the way" of Romney.

Huntsman plans to make his formal announcement on Monday in Myrtle Beach, South Carolina, where he planned to give a speech on the "broken politics" of Washington, according to the Los Angeles Times.  

Huntsman, 51, first entered the primary race last summer after serving as Obama's ambassador to China. Although he had high expectations for his campaign, Huntsman struggled during his campaign to cultivate support from conservative Republican voters.

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