Scottsville, Va. ? If Republicans are to harness enough voter anger to take control of the House this fall, they’ll have to oust freshmen lawmakers such as Tom Perriello of Virginia, who won his seat two years ago by just 727 votes.

His support for President Barack Obama’s health care and energy bills make him a White House favorite. But he’s also a prime target for Republicans in this rural, economically troubled district, which Obama lost to Republican John McCain in 2008.

First, however, Republicans must unite their own fractious base. Some tea party activists still say the GOP nominee, state Sen. Robert Hurt, is too mainstream and orthodox. One of them, Jeff Clark, is on the November ballot as an independent, and he threatens to siphon conservative votes from Hurt.

This central Virginia contest is a microcosm of competitive races nationwide that will determine whether Republicans pick up the 40 House seats they need to regain a majority in the 435-seat House after four years out of power.

Perriello, like scores of fellow Democrats, is pressed to defend his votes for health care and carbon limits — commonly known as cap and trade — to many of his constituents who see them as too costly and intrusive.

Like many GOP challengers, Hurt is criticizing those votes and hoping a rising tide of public alarm about federal debt and spending will overcome unfavorable memories of George W. Bush’s presidency. But polls show that the Republican Party remains relatively unpopular. Hurt and other GOP candidates must convince voters that Republicans have rejected their own deficit-spending habits and can manage the economy better than Democrats.

Perriello — an earnest, round-faced man with broad shoulders, a Ford pickup truck and a Yale law degree — tries to make a virtue of his votes for health care and climate change bills. Campaigning recently in a sprawling antiques store in Scottsville, he said he’s willing to take risks to help Virginians obtain medical insurance and new clean energy jobs.

Sometimes, he said, “you’re losing 400 jobs here and creating 40 here, so we’re excited about the 40. But we’re treading water right now.”

Cameron Crounse, who had invited Perriello to his River Town Antiques store, listened as the 35-year-old lawmaker told officials he’s pursuing more grants to spur economic growth. But it wasn’t clear whether the half-hour visit did anyone much good.

“I want to throw out everybody and start over,” Crounse said in an interview as Perriello was leaving.

In fact, in four hours of store-to-store campaigning in Scottsville and nearby Fork Union, it was unclear whether Perriello picked up a single vote he didn’t already have.

Hurt, 41, didn’t fare much better the next day. His problems, however, were with conservative activists rather than uncommitted centrists.

Hurt won a spirited Republican primary last month when tea party supporters split their votes rather than unite behind one hard-right candidate. A conservative by virtually any measure, Hurt is now struggling to appease those who question the fierceness of his views.

The bumps that Hurt and Perriello are finding on the campaign trail reflect nationwide discontent and suspicion among voters. The latest Washington Post-ABC News poll found that 68 percent of voters lack confidence in Democratic lawmakers, and 72 percent lack confidence in Republican lawmakers.

Only 26 percent of registered voters said they were likely to vote for their current House representative.