Updated

Many top aides of former House Speaker Newt Gingrich's presidential campaign advisors have resigned, Fox News has learned, apparently because there is no agreement on the campaign's future direction.

Gingrich, who formally announced his candidacy last month, amassed a staff of political heavy hitters. With the announcement from Gingrich's former national campaign co-chair Sonny Perdue that he has switched to Pawlenty's camp, other newly departed members of Gingrich's team will no doubt be some of the most sought-after staffers in the 2012 race. Here's a look at some of the firepower Gingrich lost.

Rob Johnson

Johnson ran Texas Governor Rick Perry's successful run last year and continued on as an advisor in Austin. Johnson joined Gingrich's camp weeks before he announced he was running for president and was ultimately named the campaign's manager. That move led some to speculate that Perry didn't have national political aspirations. Couple Johnson's resignation from Gingrich's campaign with Perry's flirtations with joining the 2012 race and there is speculation the Texas governor could run after all.

Dave Carney

One of the best known political operatives of the last thirty years, Dave Carney's Republican roots go all the way back to George H.W. Bush's presidency when he was the political director. Credited with a large role in the 1994 Republican takeover of Congress in which Gingrich took over as House speaker, he ended up working for Rick Perry as well. Carney has a wealth of experience gathered through work for Republican Senate candidates, most notably in the early presidential primary state of New Hampshire. He, too, would be an asset to Perry should the Texas Governor decide to run.

Rick Tyler

Perhaps the most shocking resignation is that of longtime Gingrich advisor and spokesperson Rick Tyler, who has been at Gingrich's side for over ten years. His departure signals a significant break in Gingrich's inner circle of loyalists.