Nearly four years after Joseph R. Biden Jr. flipped Arizona blue, the state — and in particular its largest county, Maricopa — remains a hub for debunked claims of election fraud.

In 2021, Republicans pushed for a recount of the vote in Maricopa, a lengthy and chaotic process that failed to validate former President Donald J. Trump’s false claims that the vote had been rigged. A year later, Kari Lake, a close Trump ally who lost the governor’s race, baselessly claimed that her election had been stolen, too. She attacked state and local officials and filed a series of fruitless lawsuits seeking to overturn the result. The onslaught of threats against election officials hasn’t let up since, with meetings of the Maricopa County board of supervisors, which helps administer elections, often interrupted by angry attendees.

On Tuesday, lawyers for Ms. Lake indicated she would not dispute the facts of a defamation lawsuit that Stephen Richer, the Maricopa County recorder, had filed against her. Mr. Richer, a Republican, said in his lawsuit that Ms. Lake’s unfounded claims that he had helped rig the 2022 governor’s race against her had damaged his reputation and led to death threats against him and his family.

Such election conspiracy theories are hardly unique to Arizona. But they seem to be more durable and pervasive in Maricopa County, home to Phoenix, riling up residents long after campaigns have closed up shop. Disinformation researchers and election officials suggested that a confluence of factors — Arizona’s rapidly changing status from Republican stronghold to hotly contested swing state, the lack of a prominent Republican combating conspiracy theories as one did in Georgia, and the persistent reinforcement of false information — have all contributed to an environment where baseless fraud claims run rampant on the right.

“You put that all together, and it’s a recipe for disaster,” said Joshua Garland, the interim director of the Center on Narratives, Disinformation and Strategic Influence at Arizona State University. “Once you latch onto a narrative or worldview, anything that supports or facilitates that worldview or narrative you’re much more likely to accept.”

The numbers back up Arizona’s outsize role in election fraud claims. At a news conference on Monday, Gary M. Restaino, the U.S. attorney for Arizona, said seven of the nation’s roughly 18 federal cases regarding election threats involved people targeting Arizona election officials, though the suspects are not Arizonans.

“We unfortunately are a leader in that,” Mr. Restaino said. “We expect that we are going to remain in the cross hairs, so to speak, of these threats, given that Arizona will remain a battleground state.”

The filing from Ms. Lake in the defamation case this week showed that such baseless claims can only go so far. After trying repeatedly to dismiss the case, Ms. Lake is now asking a judge to schedule a hearing to determine how much money she could owe Mr. Richer in damages, effectively bypassing a chance to fight his claims about defamation — a significant concession. Ms. Lake’s campaign said she would continue to argue that her statements did not amount to defamation at the hearing over damages, and that her move was simply an effort to expedite proceedings.

The tactic of moving straight to a hearing over damages, while unusual, would most likely limit Mr. Richer’s ability to pursue discovery in the case and potentially avoids Ms. Lake having to sit for a deposition or hand over relevant records.

Still, Mr. Richer framed Ms. Lake’s move as a victory.

“That means that the 2022 gubernatorial candidate is going to have a judgment entered into a court of law that she lied about the 2022 election,” Mr. Richer said in an interview, adding that he would seek “millions” of dollars in damages. “I set out on this course to put an end to those defamatory statements and to begin the repairing of my reputation, and so we take a step forward on those goals today.”

Mr. Richer, a Republican who now faces a primary challenger, said he had dealt with a torrent of harassment and threats since Ms. Lake began attacking him. Several people have been arrested in connection with threats of violence made against him and other election officials, and he said he had lost relationships and had to be careful about where he appeared in public.

“Not a day goes by where I don’t get to hear where traitors go, and how I should be locked up in Gitmo,” he said, referring to the Guantánamo Bay military prison.

Ms. Lake framed her decision not to keep fighting the suit as a refusal to participate in a “political witch hunt,” and used the opportunity to tie herself even closer to Mr. Trump, who has also accused Mr. Biden of weaponizing the legal system against him.

“We’ve all seen how they’re doing it to President Trump, and here in Arizona, they’re doing the exact same thing to me,” she said in a video posted to X. “I won’t be taking part.”

She added: “Even if they leave me, my husband and children homeless and penniless, that won’t stop us. We will continue to fight for Arizona.”

Ms. Lake has also gone on the offensive in recent weeks, appealing one of her lawsuits to the U.S. Supreme Court, asking it to take up her case and suggesting she had new evidence that electronic tabulation systems used to tally votes in Arizona were unreliable or prone to hacking. Past court decisions rejecting her cases have said there is no proof to substantiate her claims.

Ms. Lake’s filing asked the court to declare “that it is unconstitutional for the state to conduct an election which relies on the use of electronic voting systems to cast or tabulate the votes.”

Even aside from Ms. Lake, the Phoenix region has persisted as a breeding ground for baseless election conspiracy theories. Two Republican members of the Maricopa County board of supervisors, which tabulates votes, runs Election Day operations and certifies elections, have decided not to run for re-election this year, in part because of the hatred they faced after certifying the 2020 race for Mr. Biden and the 2022 governor’s race for Katie Hobbs, Ms. Lake’s Democratic opponent.

Critics — including Ms. Lake — accused them, without evidence, of rigging the races against the Republicans, and blamed them for the technical problems that disrupted ballot counting in 2022.

Last month, a crowd of people angry about purported voter fraud interrupted a board of supervisors meeting, forcing board members to leave early and call in the authorities to restore order. On Wednesday, the board tested new security measures, but again ended the meeting early as audience members taunted them. The board is made up of four Republicans and one Democrat.

Bill Gates, one of the retiring supervisors, said he had served in office for long enough, and he felt he could be more actively involved in administering the 2024 election if he was not also running for re-election. Mr. Gates, who said he was diagnosed with post-traumatic stress disorder stemming from nonstop harassment and death threats, said the hostile environment also played a role in his decision.

“Every day, if I just tweet, ‘I had a ham sandwich,’ the replies just pour in like, ‘You’re a traitor,’ ‘We’re going to hang you, ‘Your time is coming,’” he said. “It’s just constant.”