A man takes a picture from the top of a bus at a Tea Party Express rally. (Spencer Platt/GETTY IMAGES)

FreedomWorks also took issue with an earlier speech by Sen. Orrin Hatch (R-Utah.).

The split signifies a growing divide between two groups that represent the ‘establishment’ of the tea party movement.

FreedomWorks was founded by former House Majority Leader Dick Armey (R-Texas) and Tea Party Express was launched by longtime California GOP operative Sal Russo. Neither group shied away from backing insurgent challengers against longtime Republicans in 2010.

But Tea Party Express is a more conventional political action committee. The group is co-sponsoring a debate with CNN; it held a town hall at the National Press Club earlier this year. FreedomWorks, however, has positioned itself as a member-driven organization that will not lend its clout to anyone grassroots supporters deem too moderate.

“Our attitude has always been to keep our rallies open to everyone,” said Russo. “We even let opponents to our endorsed candidates speak. Unfortunately, some people like to feed the false image that the tea party movement is narrow-minded.”

A number of tea party groups are planning to join the Romney protest. According to New Hampshire Liberty Caucus Chairman Andrew Hemingway, the The Lakes Region Tea Party, the Raymond Tea Party, and the Granite State Patriots are all participating.

Other activists see both groups as outsiders to the movement. “They just hijacked the name,” said Jane Aitken of the Coalition of New Hampshire Taxpayers, adding that “FreedomWorks isn’t one of us either.”

And some said they were happy to see Romney speak, although they would balk at any group who endorsed him. “I’ll go listen to anybody,” said Skip Murphy, a local radio host who posts videos of candidate appearances on his blog, GraniteGrok.

The 30-city “Reclaiming America” bus tour started in Napa, Calif., and is slated to land in Tampa, Fla., on Sept. 12 in time for the CNN/Tea Party Express Republican debate.

The tour is focusing on early primary states and will host speeches by 2012 presidential contenders Romney, Michele Bachmann and potential candidate Sarah Palin.

But not only is FreedomWorks — which announced its support of the tour on Aug. 27 and has been helping turn out people for events — withdrawing support, the group will protest outside Romney’s Sept. 4 speech in Concord, N.H.

“We just can’t promote an event where Mitt Romney is speaking at a tea party rally,” said Brendan Steinhauser,  the federal and state campaigns director at FreedomWorks. “He’s the antithesis of what we stand for.”

“Folks in New England are thanking us,” Steinhauser said, explaining that the group is more in tune with grassroots activists, who support the move.

The group opposes Romney for the universal health-care legislation he implemented in Massachusetts, but also out of a general sense that the candidate is inauthentic and can’t be trusted. Romney has had little interaction with tea party groups until this point in the campaign and he is just now starting to court those activists.

A divide first opened up between FreedomWorks and the Tea Party Express over Hatch, who is expected to face a tough conservative challenge.

Russo is a former campaign consultant to the six-term senator. He invited Hatch to a tea party town hall earlier this year. In a January interview with National Review Online, Russo called Hatch “an original tea partier.”

FreedomWorks considers Hatch one of their top 2012 targets, and it is working closely with activists in the state to defeat him.

Freedom Works’ Steinhauser says the two groups could work together in the future. “This is about this tour, this event,” he said. “But they’re still friends, still part of this broader conservative movement.”

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