There's a scene in the movie "Wedding Crashers" in which the characters played by Owen Wilson and Vince Vaughn are planning the details of their scheme to infiltrate a wedding to which they haven't been invited. After hatching the plot, Wilson's character excitedly says, "Now who are we this time?"

Rep. Jason Chaffetz might feel the same way.

Chaffetz, a surrogate for Mitt Romney's campaign, remembers listening to Newt Gingrich end one of his speeches by saying that if he were the GOP's nominee for president, he would follow President Obama around to provide a Republican response.

"I thought that was a pretty good idea," Chaffetz said. "So I followed him."

Chaffetz said he talked over his plan with another congressman who supports Romney, Connie Mack, and others working for the Romney campaign. It was a go. This week, they started tailing Gingrich in Florida, crashing his campaign events to talk with ordinary people and the press.

A person close to Romney's operation, though, tells ABC News that the campaign was behind the idea from the beginning, and that a campaign staff member brought the surrogates to the press.

Their strategy is certainly controversial. Campaign operatives say they've never seen anything like it employed in a presidential campaign on this scale. Even if it is somewhat of a sideshow, the guerrilla tactics aren't exactly becoming of a front-running campaign that, at least at one point, was expected to sweep aside the competition with a well-oiled political apparatus.

"You would expect this from a campaign that's really struggling to get coverage," said Tyler Harber, a Republican strategist not associated with any presidential campaign. "I think that it could be interpreted as being a desperate move, but it really probably is not."

Political observers expect that if Romney loses the Florida primary, he'll still be in fine shape to compete handily in the next states, because his campaign operation is so much better organized than those of his rivals.

The stump crashing, however, does reflect a sense of concern in the Romney campaign that Gingrich is a more real threat than he has ever been, especially after triumphing in the South Carolina primary. Romney's lead over Gingrich in Florida has narrowed in recent polls.

Gingrich's campaign is ticked off by Romney's roving surrogates, which also include Rep. Mary Bono Mack, Rep. Rodney Alexander and the conservative activist Bay Buchanan. R.C. Hammond, Gingrich's chief spokesman, confronted Chaffetz at events on Thursday and Friday and said he plans to do the same to all of the other proxies.

On Friday, John McCain, one of Romney's highest-profile supporters, discouraged the use of a traveling rebuttal team. "I think, frankly, every candidate should have the right to hold their rallies and their campaign events without being encumbered by people who are representing other campaigns," he said.

The Romney campaign has clearly taken its attacks on Gingrich to the next level. A recent press release titled "Unhinged: Dr. Newt and Mr. Hyde" criticizes the swinging moods of Gingrich, whose mother had bipolar disorder. In Thursday's debate, Romney charged, "Speaker Gingrich was hired by Freddie Mac to promote them." The Romney campaign even got former presidential candidate Bob Dole to write a statement in which he said that in the 1990s, "Gingrich had a new idea every minute and most of them were off the wall."

"This is really aggressive," Harber said. "It has done what it is supposed to do, which is to make the Romney people look like they're aggressive and not leaving anything up to chance."

Chaffetz said that at Gingrich's events, he tries to sway undecided voters to side with Romney and talks with reporters while they're idling around - and he said he doesn't try to intentionally disrupt the campaign.

But the Utah congressman did say that when Hammond confronted him, he responded by citing Gingrich's desire to follow Obama around to rebut him. According to Chaffetz, Hammond said the situation applied only for the "actual president," not in a primary.

"I thought that was kind of silly," Chaffetz said.

Hammond said in an email that "Mitt Romney is welcome to follow us around."

Chaffetz said he'll be in Nevada next week to keep it up.

ABC News's Elicia Dover contributed to this report.