FROG JUMP, Tenn. — But for one important detail, Stephen Fincher could be a perfect “tea party” candidate: a gospel-singing cotton farmer from this tiny hamlet in western Tennessee, seeking to right the listing ship of Washington with a commitment to lower taxes and smaller government.

The detail? Fincher accepts roughly $200,000 in farm subsidies each year.

Some tea party activists say Fincher, a Republican candidate in the state’s 8th Congressional District, isn’t “pure” enough to deserve the backing of a movement built on the idea that government must spend less. But others have pledged their support, highlighting a division over what constitutes orthodoxy in the amorphous cause — and who gets to decide.

As congressional primary campaigns gear up across the nation, tea party activists face some of their first big choices since coalescing last year in opposition to President Obama, health care reform and growing federal spending: picking candidates. In many cases, they will have to decide between purity and pragmatism, between ideals and organization.

And their choices will provide clues to the long-term fate of the movement. Will mainstream Republicans, with their bigger budgets and more polished candidates, harness the tea party’s energy at the expense of home-grown activism? And for whom would that be a victory — the Republicans, the tea party or both?

“This effort is to try to get the Republican Party to try to give us more conservative candidates,” said David Nance, a Fincher supporter and founder of the Gibson County Patriots, in Jackson. “A few days ago, I was watching two candidates on one of the news channels, and basically they were kind of sparring over which one was the more conservative. Now that tells me that something’s working.”

The Tipton County Tea Party convened in the Munford municipal building on a recent evening to raise money for billboards, organize a tax day protest and encourage attendance at a state convention planned for Gatlinburg at the end of May.

About 40 people attended. They cheered when the organizer, Vince DiCello, told a long-winded joke about a new metal called Pelosium, after Democratic House Speaker Nancy Pelosi (“its mass keeps getting heavier”). And they murmured in disapproval when he passed around a photograph of Obama with his shoes off — evidence, DiCello said, that the president prays with Muslims but not Christians (“That’s because he is a Muslim,” one audience member called out).

But when DiCello asked for donations to place conservative messages on highway billboards statewide, he was met with skepticism. “Are these all going to be in West Tennessee?” one person asked. “Where is the money going?” asked another.

“We’re collecting money individually as tea party groups,” DiCello replied. Sensing the suspicion in the room, he added: “These people are not going to take our money and steal it.”

That some were unconvinced illustrates the movement’s mistrust of centralized power. But if a dozen groups across Tennessee can’t collect money for billboards, how can they organize a successful election campaign or grow into a permanent political force?

These activists mistrust Fincher because he is the anointed candidate of national Republicans and because of those farm subsidies. Jim Tomasik, a leader of the Mid-South Tea Party in Cordova, is heading perhaps the most organized effort to portray Fincher as a welfare-farmer who has received hundreds of thousands of dollars in campaign contributions from other subsidy-receiving farmers.

“If Republicans are going to complain about subsidizing General Motors, that’s a drop in the bucket to farm subsidies,” Tomasik said. “But they’re backing candidates who are taking large amounts of money from the federal government. That’s hypocritical.”

Donn Janes, an independent and self-described tea party candidate for the 8th District seat, is also among Fincher’s critics. But the challenge of competing against a well-funded candidate — Fincher has raised nearly $1 million — was highlighted in Janes’ plea for support at the Tipton County Tea Party meeting, where he invited activists to a bowling alley fundraiser.

“If you can attend, that would be great,” Janes said. “I’m not one of those guys who has a ton of special interest money.”

Fincher’s supporters are drawn to his social conservatism, including his anti-abortion stand, and his commitment to opposing new taxes (he signed the no-tax pledge of the group Americans for Tax Reform). He is more conservative than some of the other Republican candidates, but the filing deadline for the primary hasn’t passed yet.

Nance, of the Gibson County Patriots, said, “I don’t see the agricultural subsidy thing as an issue at all,” adding: “If it were an issue, then we would never elect a farmer to Congress at all. Because basically, most farmers get agriculture subsidies. If they didn’t, they’d be broke, and we’d be buying our food from China.”

Fincher, 37, a tall, blue-eyed high school graduate, had never been involved in politics until last July, when a friend asked him to run against 11-term Democratic incumbent John Tanner. He had never been to Washington until he met with Republican leaders last year, and he didn’t own a BlackBerry — though he admits he loves the one he has now.

National Republicans were giddy about Fincher’s strengths: poise and charm honed over years on the gospel circuit; a rich Tennessee drawl speckled with country aphorisms; and a surname with more than two centuries of local prominence. The icing on the cake was Fincher’s ability to raise money.

GOP strategists told Fincher he would need to raise $1 million to challenge Tanner. He quickly took in more than $300,000, an accomplishment that many observers agree was at least one factor in Tanner’s decision in December to retire. Now, Fincher has nearly $1 million in the bank, an astonishing sum for any political newcomer.

The one possible chink is the farm subsidy issue. According to data compiled by the nonprofit Environmental Working Group, Fincher and his wife, Lynn, received about $2.5 million in subsidies between 1995 and 2006. But Fincher said that without that money, his farm would have shut down years ago.

He also said the subsidies come with conditions, such as when he was required to spend thousands of dollars building an earthen terrace to control erosion.

Tomasik plans to keep beating the drum through November, a potential spoiler in a race in which the Democrat, state Sen. Roy Herron, had amassed a war chest of $655,000 as of Dec. 31. If Janes, the independent, draws even a few percentage points of support in the general election, that could make the difference in a close contest.

Fincher is acutely aware of this possibility, pleading at tea party meetings for activists to coalesce behind the strongest candidate — him — or risk a GOP loss in November.