DETROIT (AP) — First elected to Congress a quarter-century ago as a moderate Republican, House Energy and Commerce Chairman Fred Upton has been moving steadily to the right in recent years.

The question facing GOP primary voters on Aug. 7 is whether he has moved far enough to suit his southwestern Michigan district.

While Upton can boast name recognition, a huge campaign war chest and ascension to one of the most powerful jobs in the U.S. House, state lawmaker Jack Hoogendyk is hoping to pull off the upset by hammering away at Upton's conservative credentials.

Upton, though, isn't having any of it.

"Not conservative enough? I don't think so," Upton, 59, told The Associated Press after rattling off a handful of conservative organizations and figures that have endorsed his campaign.

Hoogendyk lost the Republican primary to Upton by 14 percentage points two years ago after being vastly outspent. He insists conditions might be ripe for a different outcome this time, citing strong tea party support, an "anti-incumbency mood" and a continued failure by the incumbent to display true fiscal conservatism.

"I am further to the right on regulatory policy, on social policy, fiscal policy," but the fiscal issues are the key, said Hoogendyk, who before serving three two-year state House terms starting in 2003 spent seven years as the executive director of Alternatives of Kalamazoo, a faith-based crisis pregnancy center.

"Mr. Upton is not a fiscal conservative. He's been advertising that he is," Hoogendyk said.

Among the voters Upton has convinced is former state Sen. Dale Shugars, who made an almost identical GOP run at Upton a decade ago, saying the congressman was out of touch with conservatives in the district. Upton took the threat seriously, spending heavily on the race and making the argument at the time that it wasn't "a contest to see who is the most conservative, but who is the most effective conservative." He easily defeated Shugars with two-thirds of the vote.

Ten years later, Shugars now counts himself an Upton supporter, saying in an April endorsement announcement that his former opponent's "hard work and dedication are evident in what he accomplishes for the people of southwest Michigan."

As for the chances of an upset, David Dulio, chairman of Oakland University's political science department, doesn't see it, especially considering Upton's considerable fundraising advantage.

"I don't think Upton is in any danger," he said.

None of this has deterred Hoogendyk, a 56-year-old resident of Kalamazoo County's Texas Township.

Early this year, the anti-tax Club for Growth distributed an ad that disparaged Upton as a "liberal."

Club for Growth hasn't endorsed Hoogendyk, but the Washington-based group has a history of targeting Republican incumbents it views as insufficiently conservative on tax and economic issues. The ad was critical of Upton for not supporting a Republican move to cut some of the stimulus spending pushed by Democratic President Barack Obama in 2009.

Club for Growth said that while Upton recorded a tally of 85 on the group's 2010 scorecard, his lifetime mark is only 54 percent.

Upton boasts of helping to "lead the effort to repeal" Obama's Affordable Care Act, aggressively pushing for tax relief and supporting a constitutional amendment to balance the budget. He said labels don't matter much in the 6th District, which includes Allegan, Berrien, Cass, St. Joseph and Van Buren counties as well as Kalamazoo County, which leans Democratic.

Upton, a St. Joseph resident, points out that the district has voted for the presidential winner over the past several decades with one exception: It supported Michigan's own Gerald Ford during his losing race against Jimmy Carter in 1976.

"The voters ... don't really care if you have an 'R' or a 'D' next to your name," said Upton, who first won a seat in the House in 1986 after defeating conservative Republican Rep. Mark Siljander in the primary. "They want the job done. And that's what we've tried to do."

Upton often tells voters at debates and other forums that what he has to offer is not just talk, but extensive experience navigating the waters of Washington on his home state's behalf.

As chairman of the Energy and Commerce Committee, Upton has led the charge against environmental regulations, butting heads with Obama in March when the president moved forward with a plan to place the first-ever limits on heat-trapping pollution from new power plants.

Upton also wielded influence as one of only 12 members of the deficit-reduction supercommittee, tasked with finding hundreds of billions of dollars' worth of deficit savings over the next decade.

"Being a powerful committee chair does not generally persuade voters, but it does help raise money," said Matt Grossmann, assistant professor of political science at Michigan State University.

And that certainly is the case here. Upton has plenty of campaign cash available to get the word out.

Upton, 59, had $1.89 million on hand at the end of June compared with $21,500 for Hoogendyk.

The winner of the Republican primary will face Mike O'Brien, a project team leader at furniture company Herman Miller from Douglas who served in the U.S. Marines as a platoon sergeant for special operations.

O'Brien is running unopposed on the Democratic side.