Years ago, the idea of a candidate like U.S. Rep. Tim Walz turning the conservative-leaning southern Minnesota district into a Democratic stronghold would have seemed implausible.

But the former Mankato schoolteacher and National Guardsman has built a 10-year career in Congress on an eclectic political record.

Walz is an opponent of new gun restrictions but among the earliest supporters of Democratic presidential nominee Hillary Clinton. He talks about helping immigrant populations but supported a Republican-led measure to expand background checks for Syrian and Iraqi refugees. On the Affordable Care Act, which many Democrats are criticizing, Walz is vociferously supportive.

“It is helping people,” Walz said at a recent forum of the health care law, checking off a list of advantages, such as more stable employer premiums and better coverage for those with preexisting conditions. “The issue on this is to not step forward ... and push back the progress we’ve made.”

Walz is running for his sixth term in a district that encompasses the entire southern border of Minnesota — an area Republicans had represented for all but 12 years from 1893 to 2007.

That strong Republican lean — plus polling showing presidential nominee Donald Trump’s popularity in rural areas — is why GOP challenger Jim Hagedorn says he has the best shot in years to knock off the incumbent.

“I think it’s time for a change,” said Hagedorn, a former federal employee from Blue Earth who ran against Walz two years ago and lost by 9 percentage points.

“Trump and I stand for the same bold solutions, and Hillary Clinton and Tim Walz are four more years of Obama policies.”

Minnesota’s First Congressional District is almost tailor-made for Trump, a candidate who draws the bulk of his support from white, blue-collar voters, polls locally and around the country show.

A Star Tribune Minnesota Poll in October found Trump leading Clinton by 4 points outside the Twin Cities and suburbs.

The western swath of the district is almost entirely farmers and ranchers, the eastern part is a workforce centered largely on Mayo Clinic and businesses that support it.

The district is 94 percent white, has a less than 3 percent unemployment rate and counts manufacturing as the biggest economic driver, according to the U.S. Census.

Walz, a former geography teacher and football coach at Mankato West High School, is banking on a different kind of politics to win his re-election — an approach that both openly embraces his Democratic politics but also touts his ability to work with Republicans.

He has garnered endorsements from the National Rifle Association and teachers unions and has been an outspoken advocate for veterans’ issues.

He also the highest ranking enlisted soldier to ever serve in Congress and holds a prominent position on the House Veterans Affairs Committee.

Hagedorn criticized Walz’s support for the Affordable Care Act and his oversight of a veterans health care system rocked by repeated scandals, such as negligent treatment of veterans and long wait times. Hagedorn also has vowed to take a harder line against Islamic terrorism, an area he says is of intense concern in the district’s communities that are seeing a large and rapid influx of new immigrants.

“We are at war with Islamic supremacists who adhere to the ideology of radical Islam,” Hagedorn said.

“Minnesota has a terrorist recruiting problem from existing East African refugees who were brought to the United States under the current immigration and vetting process.”

Hagedorn’s criticism about what he calls lax immigration policies mirror comments often repeated by Trump, which have been strongly embraced by some worried about terrorist attacks at home.

Former Republican U.S. Rep. Vin Weber, who represented part of Walz’s district in the 1980s, called Walz a brilliant small-town politician who will be tough to knock off.

“The Republicans have not found the candidate to make the case against him in southern Minnesota,” Weber said.

“It’s pretty hard to dislodge people’s loyalties for [Walz]. That’s his advantage. He’s to the left of his district, but he’s a congressman in a district with a small-town culture.”

Unapologetic

Such praise has fueled speculation that Walz might run for governor or the U.S. Senate if a seat opened up.

Outgoing DFL state Rep. Kim Norton, who lives in Rochester, said she has seen Walz talk to a room of people who disagree with him and eventually win them over.

“When he does defend Hillary or the ACA, he does it unapologetically and he does it with passion and fervor and a belief in it that is convincing,” she said.

On health care, state Sen. David Senjem, a Republican who represents the area north and west of Rochester, said Walz’s devotion to the health care law may hurt him at the ballot box.

Hagedorn keeps hammering his rival on the issue, saying voting for the health care law was Walz’s worst decision in Congress.

“People who may be dropped by Blue Cross Blue Shield, farmers on individual policies grasping for help and confronting huge premiums and deductibles,” Senjem said. “I think everyone has concerns about the direction that we’re going and the kind of situations we hear.”

Walz acknowledges work needs to be done to fix the problems with the individual marketplace and rate hikes, but he directs criticism at House Republicans for continuing to vote on repealing ACA without making improvements.

“Why are we not taking votes to improve?” he asked at a debate with Hagedorn in Mankato in October. “This same debate happened with Medicare. Had we not improved Medicare, would the solution be to repeal Medicare? Or improve Medicare like we did? And the ACA falls in that same category.”