DE SOTO, Kan. (AP) — The sheriff in Kansas’ most populous county faced no opposition to his reelection four years ago, extending a decades-long Republican lock on the office despite big gains locally by Democrats during the Trump era. Then he took on election fraud as a cause.

The GOP in Johnson County in the Kansas City area is deeply divided over Sheriff Calvin Hayden’s investigation for at least two years into what he has called scores of tips about potential election irregularities, with no criminal charges filed so far.

Hayden is in a contentious race ahead of Tuesday’s primary election and Democrats are bullish about their chances of winning their first sheriff’s race since 1930 in the general election in November.

Hayden’s opponents, including the former top deputy challenging him in the GOP primary, contend he has made the sheriff’s office unnecessarily political and hindered its crime-fighting.

His public doubts about the integrity of local and state elections track with the rise of like-minded leaders in GOP organizations in Kansas and other states and former President Donald Trump’s false narrative that the 2020 presidential election was stolen from him.

But local Republican leaders who looked into allegations of election fraud in 2020 say evidence of wrongdoing was scant.

Marisel Walston, the previous chair of the county GOP and co-founder a statewide group for Hispanic Republicans, said she and other local party officers investigated allegations of election fraud after the 2020 election. While they discovered some mistakes and administrative missteps, they did not find any fraud, she said.

Hayden remains undeterred. Asked in a candidate forum whether he trusted the 2020 election results, he noted the official tally from his uncontested race was more than 260,000 votes but added, “I don’t know that that’s accurate.”

As in other suburban areas across the U.S., a pro-Trump pedigree is likely to be a political liability in November in Johnson County, a former GOP stronghold where Democratic voter registrations have grown nine times faster than Republican ones since 2016. But the GOP primary electorate in Kansas is far redder and more pro-Trump.

“We’ve had, obviously, a lot of moderates move to being independent or just stop voting in primaries,” said former state Rep. Stephanie Sharp, a moderate Republican. “I don’t think that there’s enough moderates who vote in primaries anymore to get moderates out in primaries.”

Voters are set to pick the major party nominees for Kansas’ four congressional seats, all 40 state Senate and 125 state House seats and offices in the state’s 105 counties.

Hayden is a former Army reservist who joined the sheriff’s department in 1981 and rose through the ranks until he won a seat on the county commission in 2008, serving one four-year term. He won a three-way Republican primary for sheriff in 2016, with no Democrat on the ballot.

He argues that installing a new sheriff is risky.

“We’ve kept Johnson County safe,” he said during a July candidate forum. “I’ll stand on my record.”

Hayden confirmed his voter fraud investigation in 2022, saying he had been receiving tips about problems since the previous fall. Then, in the summer of 2022, he participated in a conference for a group promoting a dubious theory that sheriffs have virtually unchecked power in their counties, though he says he is not a member.

Last month, Hayden said he suspended the investigation, blaming the county’s destruction in February of ballots from 2019, 2020 and 2021, which is at least 17 months late but in line with state law.

Hayden’s office referred questions over his work as sheriff to his campaign, which did not respond to a request for an interview.

In his primary race, Hayden faces Doug Bedford, a former U.S. Navy Seal and longtime sheriff’s officer who served as Hayden’s undersheriff from 2017 to 2021 before retiring and becoming a state liquor control officer.

Bedford suggested the sheriff has broken with a tradition of his office’s 700 employees being “silent professionals” who avoid public attention.

“Now it almost seems like that is the goal is to be in the news,” he said during an interview at the Veterans of Foreign War hall in his hometown of De Soto on the western edge of the Kansas City area.

The winner of the Republican primary will face Democrat Bryan Roberson, the police chief in the suburb of Prairie Village, whose office decor includes a cartoon portrait by “The Simpons” creator Matt Groening. The former Marine reservist would be Johnson County’s first Black sheriff if he won.

Roberson said he believes Hayden’s voter fraud investigation reflected badly on local law enforcement.

“I’m all for investigating crimes,” he said. “But if there is no information to prove a crime, you can’t keep it open.”

For at least two decades, Johnson County’s rate for violent crimes — murder, rape, robbery and aggravated assault — has remained well below the state’s, according to data in annual Kansas Bureau of Investigation reports. The murder rate has ticked up since Hayden took office from 1 to 2.2 per 100,000 residents, but all of the county’s 14 reported murders in 2023 were in areas outside his jurisdiction.

The county population’s has grown 75% over the past 30 years to more than 620,000. It’s also more diverse: previously 94% white and non-Hispanic, now 77%.

The GOP gap in voter registration once was nearly 26 percentage points and is now 8.5 points. In an August 2022 statewide referendum, 69% voted to affirm abortion rights.

“You look at what used to be this mighty, dominant Republican base in Johnson County, and it’s just hemorrhaging voters that either unaffiliate or flip Democrat or they just start voting for Democrats,” said Cole Robinson, executive director of the county Democratic Party.

While Trump is expected to carry Kansas comfortably again this year, he’s likely to lose Johnson County after losing it by about 8 percentage points in 2020. He was the first GOP presidential candidate to fail there since 1916.

Hayden has said he took it for granted that local elections ran smoothly until Trump’s showing in 2020. He said in the recent candidate forum that his office is still receiving tips and complaints about election problems “every day.”

Hayden’s supporters see the criticism of his efforts on election fraud as an unwarranted campaign to discredit him.

“I believe election integrity is the absolute root cause of all of the maladies in our country right now,” said Kay Shirley, a GOP volunteer in Johnson County backing Hayden. ”It got my attention when I saw that he was willing to stick his head out and his neck out, and he just listened and he paid attention.”

But even some longtime conservative Republican activists have broken with Hayden after backing him previously.

Watson, the former county GOP chair, said she believes Hayden’s actions and public comments have eroded confidence in local elections and discouraged people from voting.

“I was very disappointed in him,” she said. “I was totally surprised that he was lending himself to that sort of thing.”