BEDFORD, Pa. -- Art Halvorson makes for an unlikely Republican primary challenger to a six-term incumbent like Rep. Bill Shuster. He is a newcomer to this quiet corner of south-central Pennsylvania who retired after a long Coast Guard career.
But in the throw-out-the-bums anger percolating in the election cycle now underway, Mr. Halvorson, 58, believes he might have a shot to displace a family name that has occupied this district's House seat since Mr. Shuster's father, Bud, won it in 1973. After two House elections dominated by the small-government philosophy of the Tea Party, 2014 may be driven by a less ideological but more emotional sentiment: Clean house.
"People don't remember a time before the Shusters," Mr. Halvorson said. "They created an aristocracy, and people are so accustomed to that's the way politics is done around here, they don't see how he can be toppled. I've got to show leadership's what's important, not seniority, and longevity is not leadership."
The outcome of this and at least 17 other primaries next year may have a negligible impact on Republican control of the House.
Few would suggest that Pennsylvania's 9th Congressional District -- which includes Indiana, Cambria, Blair, Bedford, Somerset, Fayette, Green, and Washington counties -- is in danger of slipping into Democratic hands. But in the heated battle over the ideological future of the Republican Party, races like this one could alter the complexion of the Republican caucus in the House -- and Washington's ability to govern in President Barack Obama's final years in office.
"That's the narrative everybody wants to know: What's the Republican Party going to look like after Ted Cruz-Tea Party people get done with it?" Mr. Halvorson asked, eschewing the Tea Party label even as he adopts many of its campaign tropes. "Who's going to have the ascendancy?"
From Tennessee to Michigan to Oregon, House Republican incumbents are facing an onslaught of primary challenges. But unlike the past two election cycles, there is almost no ideological pattern to the contests.
Reps. Justin Amash and Kerry Bentivolio of Michigan and Scott DesJarlais of Tennessee -- all Tea Party lawmakers in good standing -- are threatened by potential challengers backed by business groups and their more traditional Republican allies. Those challenges are not so much from the party's left but more from a new breed of candidates hoping to "professionalize" a House Republican caucus whose image has been battered by the turmoil in Washington.
Even the chairman of the National Republican Congressional Committee, Greg Walden of Oregon, has drawn a credible challenger from the party's right, Dennis Linthicum, the chairman of the Klamath County Board of Commissioners.
How such contests resolve themselves could leave the House Republican caucus either more uncompromisingly conservative in 2015 or more committed to governance and compromise.
"It's an offshoot of the decline in competitive districts because of redistricting," said David Wasserman, a House analyst at the nonpartisan Cook Political Report. "There are fewer fights to pick with the other party, so there are going to be more fights within your party."
In some sense, the fight for the heart of the House Republican caucus began Tuesday in Alabama, when Bradley Byrne, a business-backed former state senator, fought off a Tea Party-supported firebrand to win a special House election in Mobile.
In bordering Tennessee, Mr. DesJarlais has maintained his Tea Party bona fides since the 2010 wave swept him into Congress. But the taint of scandal has followed him since divorce records exposed accusations of violent behavior as well as a telephone transcript indicating that as a practicing doctor he had an affair with a patient and encouraged her to get an abortion. Another former patient emerged last year to say that she, too, had had an affair with Mr. DesJarlais and had smoked marijuana with him.
The hits have kept coming since then, and state Sen. Jim Tracy is now considered the favorite in the primary fight in August.
In Michigan, business-backed candidates are taking aim at Mr. Amash and Mr. Bentivolio, two black sheep of the House Republican conference. Mr. Amash has electrified the libertarian wing of the Republican Party with his crusade against domestic spying, his willingness to challenge his party's defense hawks and his opposition to even the most austere budget plans of his leadership, which he invariably condemns as timid taps at the Big Government edifice.
But his showy image as the House's "Dr. No" has angered the button-down business community of Grand Rapids, long used to the quiet conservatism of Vernon Ehlers, a physicist who served in Mr. Amash's seat for 16 years without making much of a ripple. Brian Ellis, a Grand Rapids businessman, has won the support of several high-profile businesspeople.
"He's not a conservative Republican; he's a libertarian," Mr. Ellis said of his opponent, insisting that a district that turned in 2010 to a Ron Paul-inspired provocateur from Mr. Ehlers has not changed as much as its representation has. "I'm putting my campaign on the line to say that's not the case, and we're going to find out."
On the other side of Michigan, Mr. Bentivolio is an accidental congressman, elected last year after the popular Republican incumbent, Thaddeus McCotter, resigned suddenly because most of the signatures his campaign had collected to put him on the ballot were proved fraudulent.
Mr. Bentivolio, who once raised reindeer, starred in a homemade movie that accused George W. Bush of planning 9/11 and once said in court that he sometimes could not tell whether he was Kerry Bentivolio or Santa Claus. But as the only Republican left on the ballot, he won.
In his year in office, he has kept a low profile. But the Eastern Michigan establishment is still seeking to oust him, and its members are backing a lawyer and businessman, Dave Trott.