FLAGSTAFF, Ariz./DALLAS (Reuters) - A grassroots conservative campaign against the Obama administration’s healthcare reform plan has galvanized Republicans but also exposed the party to charges it is a captive of the fringe.

Republicans, who suffered overwhelming defeat in elections in 2006 and 2008 and are the minority in Congress, have taken heart this summer from a wave of townhall meetings and rallies that highlighted public uncertainty about the plan.

Although it was doubtful that Republicans ever would support healthcare reform, the signature issue of President Barack Obama’s agenda, protests by key members of the party’s base have made it even more difficult to do so.

At the same time, many Americans say they want some sort of healthcare reform pushed through. Republicans risk the wrath of voters if Democrats successfully brand them as obstructionist and pass a reform bill without their support.

The dilemma was apparent Monday night in Flagstaff, Arizona when hundreds of supporters gathered to greet “The Tea Party Express,” an anti-government bus group touring the nation en route to a final rally in Washington, D.C. on September 12.

“Impeach the Fascist Dictator,” read a sign carried by Vicki Grant, a 59-year-old real estate investor.

“I think it’s atrocious, and any government program is bound to fail. They all fail,” Grant said of Obama’s plan. “Anytime you get the government involved in anything it’s a mistake. Free market is ... what made America great.”

Others at the rally toted signs that read: “Hands Off My Healthcare” and “Kill the Obamacare bill.”

John Echols, 38, a political consultant and one of the event’s organizers, said it was a non-partisan affair, but analysts say such protests, following weeks of often rowdy demonstrations, were not lost on Republicans.

HEALTHCARE RADIOACTIVE FOR REPUBLICANS

“They have made the healthcare bills radioactive for Republicans,” said Dennis Goldford, a political scientist at Drake University in Des Moines, Iowa.

He added that Republicans were reeling after losing congressional seats in 2006 and the White House in 2008 and were vulnerable to arguments from conservative elements that they had become too mainstream.

“The Republicans are so disorganized and here’s the one group claiming some Republican alliance. And they are the ones with the passion and the energy in the Republican Party. The party is riding a tiger and the question will be whether they can control these people or not,” Goldford said.

Conservative talk radio hosts and others have helped stoke opposition to Obama’s plan by charging that it is a socialist takeover of healthcare that will spur abortion by providing federal funding for the procedure.

Obama and his supporters have denied the charges and say the changes are simply aimed at improving the healthcare system, mainly by providing coverage to the roughly 46 million Americans with no medical insurance.

But the criticism has helped rally conservatives, including conservative Christians, who remain a key part of the Republican base.

Some analysts said conservative activists are unlikely to sway independent voters not to mention Democrats in Congress, who may cobble together enough votes to pass healthcare legislation after Congress resumes next week.

“They’re speaking to the choir ... all it really does is reinforce their own positions ... but it doesn’t affect any significant portion of the population,” said Bruce Merrill, a political analyst at Arizona State University in Phoenix.

Cal Jillson, a political scientist at Southern Methodist University in Dallas, said he could envision a scenario in which Democrats pass a bill including a “trigger” to phase in a public insurance option if private companies did not reduce costs or introduce other reforms.

That is unacceptable to Mike Strohmeyer.

“I don’t think it will work ... It’s super expensive and our healthcare will suffer, it will get phased out,” the 55-year-old police officer said at the rally in Flagstaff.