Tea party Rep. Tim Huelskamp heading to defeat in Kansas Republican primary | McClatchy Washington Bureau

Voters in Kansas’ 1st Congressional District primary faced a contrasting choice between two Republicans, though more in personality than politics.

And based on early returns Tuesday night, they chose newcomer Roger Marshall over three-term incumbent Rep. Tim Huelskamp, one of the most outspoken conservatives in Congress.

At 10 p.m. Central Time with half the precincts reporting, Marshall led Huelskamp 57 percent to 43 percent, according to unofficial results from the Kansas Secretary of State’s office.

Marshall led in many of the far western Kansas counties where Huelskamp had won his last Republican primary in 2014. Among the few counties the conservative lawmaker carried: Seward, along the state’s southern border, which includes the city of Liberal.

Earlier in the evening, multiple TV and newspaper reporters were kicked out of Huelskamp’s “victory” headquarters in Hutchinson, with little explanation offered.

Huelskamp would be the third Republican House incumbent to lose this year. As with the other two races, redistricting played a role. On most issues, be it Obamacare, the Second Amendment or Planned Parenthood, Huelskamp and Marshall weren’t that far apart.

But Huelskamp’s confrontational, anti-establishment approach had turned off his colleagues on Capitol Hill as well as many farm groups back in the sprawling, 63-county district he represented.

“I think his personality is the underlying issue,” said Patrick Miller, an assistant professor of political science at the University of Kansas, of Huelskamp. “He has a combative, often controversial, sometimes divisive approach to politics that doesn’t sit well with some Republicans.”

In some ways, the differences in the candidates and their supporters reflected the divide within Republican ranks on Capitol Hill. Business groups saw in Marshall a candidate more likely to work with House leaders to get legislation passed. Tea party and libertarian groups saw in Huelskamp a principled conservative eager to buck Washington’s norms.

“You love him or you hate him,” Miller said.

Huelskamp’s style, though popular with some voters, went against the grain for a district that had sent pragmatic conservatives to Congress over the course of 50 years: Bob Dole, Keith Sebelius, Pat Roberts and Jerry Moran.

Huelskamp’s votes on key issues and his 2012 removal from the House Agriculture Committee pushed the district’s ag interests into the Marshall camp.

Marshall got a boost from the Kansas Farm Bureau’s endorsement last month, and last week gained the backing of the U.S. Chamber of Commerce.

Huelskamp had the support of anti-abortion and gun-rights groups, as well as the Club for Growth and the National Federation of Independent Business.

The two candidates raised a similar amount of funds from donors, about $700,000 each. Marshall, a physician, loaned his campaign another $199,000.

Marshall and Huelskamp fought in debates and over the airwaves. A Huelskamp ad rehashed a 2008 incident in which Marshall pleaded no contest to reckless driving and paid a fine after a neighbor accused Marshall of trying to run him over with a pickup truck.

Marshall accused Huelskamp of not even living in the district and filed a challenge to Huelskamp’s eligibility to run there. Kansas Secretary of State Kris Kobach dismissed Marshall’s claim.

Huelskamp claimed that Marshall, a physician, would reap the benefits of President Barack Obama’s signature health-care law, something both candidates oppose.

He also claimed that Marshall belongs to a medical professional association that backs Planned Parenthood. Both candidates oppose abortion.

Marshall tried to use Huelskamp’s 1995 doctoral dissertation at American University, in which he opposed the very agricultural subsidies and price supports that benefit his district, against him.

Marshall tied that to Huelskamp’s votes against the 2014 Farm Bill, though every member of the Kansas delegation except for Republican Sen. Jerry Moran opposed the final version.

Huelskamp dismissed Marshall’s qualifications to be on the agriculture committee, though he and Marshall both own farm interests.

Huelskamp had asserted that he would be reappointed to the Agriculture Committee under House Speaker Paul Ryan. Ryan had not publicly made that commitment, however.

The race drew millions of dollars in outside money, including $400,000 from the U.S. Chamber alone.

In a statement, Rob Engstrom, the chamber’s national political director, called Marshall’s victory “decisive.”

“Governing was on the ballot,” he said in a statement Tuesday, “and voters spoke clearly.”

It’s the only race in the country where the business lobby was actively working to defeat a Republican incumbent. Only two Republican incumbents have lost House races this year.

The ESA Fund, backed by wealthy philanthropists, spent $1.2 million on radio and TV ads, digital media and full-page newspaper ads.

Brian Baker, the fund’s president, noted that Marshall trailed Huelskamp just a month ago before it launched the blitz.

“Incumbents very rarely lose, which tells us that voters are demanding that Republicans in Congress work together to advance a fiscally conservative agenda to actually end out-of-control spending,” Baker said in a statement, “not just grandstand.”

Huelskamp was elected in 2010’s tea party rout that brought Republicans into the majority in the House, with John Boehner as speaker. However, Huelskamp and other conservative lawmakers who came in at the same time gave Boehner little but headaches. They almost forced the government to default on its debt in 2011 and go over the “fiscal cliff” in 2012.

They did force a government shutdown in 2013 and last year drove Boehner out of Congress.

In the 2014 Republican primary, school administrator Alan LaPolice came within 10 percentage points of defeating Huelskamp.

Farm groups held off endorsing a candidate in the primary in 2014, but this year have uniformly lined up behind Marshall.

Huelskamp was the only incumbent Republican member of Congress to not get the Kansas Farm Bureau’s support.

It wasn’t just farm interests at stake.

“I wouldn’t say it’s all that matters there,” said Miller, of the University of Kansas.

The district’s boundaries were redrawn after the 2010 Census to reflect the loss of population in far western Kansas. The district now includes one of the state’s largest public universities, Kansas State, as well as one of its largest military bases, Fort Riley.

Those institutions rely on the kind of government spending Huelskamp has railed against.

Bryan Lowry of the Wichita Eagle contributed to this story.