The former campaign manager for Jon Huntsman's presidential campaign has signed on with Mitt Romney.

Susie Wiles, who previously served as Huntsman's campaign manager before leaving the campaign after clashing with fellow staffers, will serve as co-chairwoman of Romney's Florida Advisory Council.

"As this campaign has progressed, I have had an opportunity to observe each of the candidates, and it is clear to me that one candidate stands out from the rest: Mitt Romney," Wiles said in a statement on Monday. "Gov. Romney is a conservative businessman who knows what it takes to turn our economy around. He has demonstrated the stability, intellect and integrity that Republicans are looking for in their standard-bearer. And perhaps most importantly, he will take the battle to President Obama's doorstep and ensure that Barack Obama is a one-term president."

In announcing Wiles joining his campaign, Romney said she has been a strong "leader and advocate in Florida."

"On the issues that I have been fighting for in my campaign, Susie has been a leader and advocate in Florida and across the country for years," Romney said. "I am proud to have her support."

The endorsement shows that with Newt Gingrich attracting conservative Republican voters, Romney wants to ensure he has the moderate Republican vote. In a statement, Huntsman's campaign said the Romney campaign's announcement of Huntsman's support showed that the former Massachusetts governor is worried about New Hampshire.

"Governor Romney's unusual announcement of a paid political consultant's endorsement shows that they are concerned about Jon Huntsman's New Hampshire momentum as voters tune in to his consistent conservative message," Huntsman spokesman Tim Miller said.

Also on Monday, MSNBC reported that Richard Brothers, an early Huntsman supporter and campaign consultant announced he was leaving the campaign to back Newt Gingrich. Brothers, according to MSNBC, accused the campaign of failing to pay him. Miller denied that any of Brothers's accusations were true.

"Richard Brothers had left the campaign and his accusations are false, we wish him the best in his future endeavors," Miller said according to NBC News.

—This story was updated at 10:14 a.m.