NELIGH, Neb. - One recent still summer night in this tiny city on the Nebraska prairie, more than 60 people showed up at a senior citizens center to hear attorney David Clements warn of an epidemic of purported election fraud.

For two hours, Clements - who has the rumpled look of an academic, though he lost his business school professor's job last fall for refusing to wear a mask in class - spoke of breached voting machines, voter roll manipulation and ballot stuffing that he claims cost former president Donald Trump victory in 2020. The audience, which included a local minister, a bank teller and farmers in their overalls, gasped in horror or whispered "wow" with each new claim.

"We've never experienced a national coup," he told the crowd, standing before red, white and blue signs strung up alongside a bingo board. "And that's what we had."

Clements, who has no formal training or background in election systems, spent months crisscrossing the back roads in his home state of New Mexico in a battered Buick, trying to convince local leaders not to certify election results. His words had an impact: In June, officials in three New Mexico counties where he made his case either delayed or voted against certification of this year's primary results, even though there was no credible evidence of problems with the vote.

Now, Clements has taken his message nationwide, traveling to small towns in more than a dozen states, with a focus, he said, on places that are "forgotten and abandoned and overlooked." His crusade to prove that voting systems can't be trusted has deepened fears among election experts, who say his claims could give Trump allies more fodder to try to disrupt elections in November and beyond.

Republican primary candidates embracing Trump's stolen election rhetoric have flourished this year. Clements's strategy is to target his message locally: to county commissioners and clerks, jobs that are lower profile but that wield an outsize role in administering America's decentralized election system. If local jurisdictions fail to certify their votes, it could throw the outcome of an election into chaos, raising doubt about the results and giving ammunition to losing candidates who refuse to accept their defeat.

Clements is one among a tightknit circle of Trump supporters who travel the country as self-appointed election fraud evangelists. They embrace the instructions of leaders like former Trump adviser turned podcaster Stephen K. Bannon, who has urged election deniers to run for local races and sign up to be poll workers in what he calls his "precinct-by-precinct" takeover strategy.

Like others preaching the gospel of election fraud, Clements has attracted a large following online, where he mixes conspiracies with Christian nationalist and sometimes violent rhetoric. He has appeared on Fox News and on Bannon's podcast. He's dined with Trump and Mike Lindell, the chief executive of MyPillow and high-profile election fraud conspiracist.

"We've got enough evidence to have indictments, people tried for treason and have the remedy of firing squads. That's what we need," Clements told an audience at a New Mexico church in February.

A recent report from congressional Democrats on election misinformation highlighted Clements' activities, and concluded that "the greatest current threat to democratic legitimacy now comes from lies by domestic actors who seek to convince Americans that their election systems are fraudulent, corrupt, or insecure."

New Mexico Secretary of State Maggie Toulouse Oliver, who has clashed repeatedly with Clements and his wife, said the "misinformation and disinformation" were being "seeded as core beliefs, not just with elected officials but the general public."

"I do worry about potential violence toward election officials, in particular around the upcoming general election," she said.

Clements said in a brief interview in Nebraska that he believes his efforts are noble.

"Why?" he asked. "Because I care about the truth. Because I want to make sure our voices are accurately captured. Because the rule of law needs to exist."

Pacing the room at the senior center in Neligh, microphone in hand, Clements put the matter in stark terms.

"We've figured out how they're screwing you out of your vote," Clements said. "That's the battle. So what's the solution?"

"Sledgehammers!" a woman at the back of the room yelled out.

Clements, 42, was a popular tenure-track assistant professor teaching law in the business school of New Mexico State University on Jan. 6, 2021, when a mob loyal to Trump stormed the U.S. Capitol. As news of the attack came, he was in his cabin in the mountains of New Mexico with his wife and three young children.

Distraught that Biden's victory would be validated by Congress despite the riot, he has said that he ran outside and fell on his knees, next to the fire pit.

"I said, 'God save us, please, please save our country,' " he recalled in a speech in Michigan last year. He looked back and saw his wife and children standing in the window watching him, weeping. "And something happened. My heart filled . . . and I heard, 'We are going to win.' "

Clements came down from the mountain filled with zeal and - sitting down in his garage armed with nothing more than a laptop and a "crappy microphone" - soon began posting about alleged election fraud on YouTube. He said he began examining the alleged evidence of fraud in contested states like Georgia and Pennsylvania in the days following the election, and later had some of those who claimed to have observed it firsthand appear on his YouTube videos.

Clements said in an interview that as an attorney he was "eminently qualified" to talk about the legalities surrounding voting machines, and that his wife, Erin, has two decades of expertise working with data as a civil engineer. Neither, however, has experience running elections or formal education in voting machine systems.

No fewer than 86 judges rejected at least one post-election lawsuit filed by Trump or his supporters, a Washington Post review of court filings found.

Clements, who was born in Seattle, grew up the child of itinerant parents who worked blue-collar jobs. Early in his life, he struggled with drugs, alcohol and an assault conviction, he has said.

"I'm a child of the trailer park. My mom worked at Kmart and Lowe's, my dad bagged groceries," he said. "Dysfunctional family. At times I felt cursed. I'd see other happy families on vacation while I would bus their tables as an underage kid and say, 'is this it, Lord?' "

But, he said he realized, "God was preparing me for something, to see artifice, to see lies."

He delved into politics too, serving as a county Republican chair and as an unsuccessful Republican primary candidate for the U.S. Senate in 2014. Later, he served as the vice chair for legal affairs of the state's Libertarian party.

At New Mexico State University, Clements was known for his engaging lectures, being available to students and grading papers late into the night, according to David Pecchia, a former student and retired Air Force master sergeant who was close to Clements and considered him a mentor. Pecchia wrote a recommendation letter for Clements for a teaching award that recognizes excellence in pre-tenure professors. Clements won last year.

Just weeks later, in October 2021, he was fired, by his own account, for refusing to wear a mask in class. In his disciplinary hearing, which Clements posted online, the university said he violated the school's covid-19 mask and vaccination policy.

Pecchia said his respect for Clements evaporated one day when he saw his former teacher leading an anti-mask march through a craft market where Pecchia sold his woodworking, causing a disturbance.

"Clements was saying, 'You're zombies, man. You're zombies,' " Pecchia recalled. "This guy has gone off the deep end. It's like he's been radicalized somehow. It was a complete change. I never ever got the impression he was so radical about things like that and I felt stupid I had submitted a letter for this guy nominating him for this great award."

Anti-vaxxers quickly embraced Clements, with far-right Colorado podcaster Joe Oltmann creating an online fundraiser for him and calling him "a lightning rod of truth and courage." The appeal has since brought in more than $304,000 in donations, including from donors who say they support his "election integrity" crusade. Clements says he is not paid for his appearances but asks for donations for travel expenses at the door.

As his zeal over election fraud heightened, other associates fell away.

"Given his intelligence and accomplishments, the fact that he's decided to pursue this provably false theory is tragic and surprising," said Chris Luchini, the head of the Libertarian Party of New Mexico and a former colleague of Clements.

In October, around the time he was fired from his university job, David and Erin Clements mailed a 261-page document to commissioners and county clerks across New Mexico alleging widespread issues with the voting systems - what the congressional report called "imaginary fraud."

Asked for comment, Erin Clements sent a video of Democratic lawmakers raising concerns about election security. Many of the comments predated the 2020 election and focused on the potential for foreign interference. The U.S. intelligence community has continued to warn that foreign actors are likely targeting American elections.

David and Erin Clements claimed that the state's voting tabulators are insecure and miscount votes. They also alleged that unnamed bad actors "massively" manipulated voter registration rolls, allowing people to illicitly vote in the last presidential election.

The couple soon found an ally in Couy Griffin, a flamboyant former Disneyland Paris rodeo cowboy who until this week was a member of the county commission in Otero, a rural New Mexico community of 69,000 along the Texas border. Griffin, who was once thanked by Trump for saying "The only good Democrat is a dead Democrat" and who was convicted of a misdemeanor for entering a restricted area during the Capitol riot, has long alleged the 2020 presidential election was stolen. A state judge on Tuesday ordered Griffin removed from office, citing his role in having "aided the insurrection" on Jan. 6, 2021.

"This is a nonpartisan issue," Griffin said in an interview. "Whether you are a Democrat or a Republican we should all want to make sure our elections are secure."

Griffin said David Clements "knows what he's talking about," and that he is the kind of expert Griffin wants to explain complicated voting systems to him, rather than the election officials in his own county.

By March, volunteers organized by David and Erin Clements calling themselves the New Mexico Audit Force were going door-to-door in Otero County asking citizens about how they voted in 2020. The canvass was part of a controversial third-party audit that commissioners had voted to spend nearly $50,000 on in January, despite the fact that the county went overwhelmingly for Trump, with the incumbent winning nearly 62 percent of the vote.

The effort sparked a voter intimidation inquiry by the House Oversight Committee. The audit later fell apart, with the firm hired to analyze the results agreeing to return part of its initial payment, stipulating they had found no evidence of fraud.

But David and Erin Clements pressed on, appearing before the three-member, all-Republican Otero commission with a new target: the state's June 7 primary. David Clements urged commissioners not to perform their statutory duty to certify the results, arguing that doing so would place them in legal jeopardy because of the problems they alleged with the machines. The county's attorney disagreed, calling the argument "highly unlikely."

Yet two independent election security experts who have examined the Clements' work - Susan Greenhalgh, senior adviser on election security for the nonprofit Free Speech For People, and Kevin Skoglund, president and chief technologist for the nonpartisan Citizens for Better Elections - said the fraud charges are baseless and misleading. New Mexico's Secretary of State has also rejected the allegations.

A document that David Clements claims shows a failure to update voter check-in machines for 11 years is inaccurate, since the state uses a different check-in system, the Secretary of State's office said.

The claim that the volunteer canvassers found dozens of "ghost voters" at one address turned out to reference the post office box at a nearby military base.

Clements also asserted that the digital file containing the ballot from the 2020 elections had been deliberately "wiped" from the voting machines when in fact separate files are created for each election and the ballots and other records are preserved.

"Their reports on election fraud are a jumble of conspiracy theories and full of errors. They are wrong about voting technology, election processes, certification, and legal requirements," Skoglund said. "They even quote me and cite my work on voting systems with modems and internet connectivity, but I disagree with every conclusion they draw from my work."

"I don't think he understands what he's talking about most of the time," said Greenhalgh. "He takes things and extrapolates them to a place that comes completely out of thin air. It sounds good and people believe it because it sounds authoritative if you don't know much."

The "fanciful arguments" of conspiracists obscure the country's real need to continue to address election vulnerabilities, she said, such as internet voting - 31 states and the District of Columbia allow it for overseas, military and in some places disabled voters - as well as outdated paperless voting machines.

Clements' allegations extend to voting machines made by multiple companies, including Dominion Voting Systems, which are used in New Mexico and have been the target of claims by Trump supporters. Those claims are rooted in a 2020 election night error by the clerk in a Michigan county that resulted in the heavily Republican area briefly reporting that Biden had beaten Trump there. The error was quickly corrected, but the damage was done.

Dominion officials have denied all allegations made against the company, filing multibillion-dollar defamation lawsuits against various people who spread the claims.

"This is yet another example of how lies about Dominion have damaged our company and diminished the public's faith in elections," Dominion spokeswoman Stephanie Walstrom said of Clements.

At the June hearing in Otero, David and Erin Clements turned up to a crowded meeting room to give the commission a nearly three-hour update on their "findings." The couple's conclusions prompted Griffin to chastise his own clerk, Robyn Holmes, a Republican who has thirty years of experience running elections in the county.

"If I was in your position I wouldn't be able to sleep at night," Griffin said to Holmes. "You're in the middle of elections that are fraudulent right now if what they're telling us is true."

"If what they're telling us is true," Holmes said, shouting, "IF!"

Toward the end of the meeting, Donna Swanson, a former presiding poll judge in Otero County who worked with Holmes for years, stepped up to speak.

"I totally take exception to the idea that Robyn Holmes - our Republican clerk - doesn't know what she's doing. So who is the leader here today?" Swanson asked. "Is it my county commissioners or these people sitting here who had lunch with Donald Trump and the MyPillow guy?"

On June 17, the state's deadline to certify election results, Clements drove several hundred miles in his old Buick, hoping to stop commissions across New Mexico from okay'ing the votes. He appeared first in Torrance County, where he led off comments at a raucous meeting. Citizens hurled insults at leaders voting for certification, calling them "cowards," "traitors to our country" and "rubber stamp puppets."

In Sandoval County, Clements had so riled residents that the commissioners had to be removed from the hearing room by sheriff's deputies for their safety after voting 4-1 to approve the results, according to County Commissioner Katherine Bruch, a Democrat.

In Otero, two commissioners who had voted not to certify earlier in the week reversed their decisions and approved the results, bowing to an emergency order from the state's Supreme Court that mandated them to follow their statutory duty.

Griffin, the only dissenter, called his vote in from Washington, where he had just been sentenced to 14 days in jail - time served - for his role in the Capitol attack.

"My vote to remain a no isn't based on any evidence, it's not based on any facts, it's only based on my gut feeling and my own intuition, and that's all I need," Griffin said, his drawl tinny on the speakerphone.

The Otero controversy is far from over. On Aug. 11, Clements and his wife presented the final findings of their "audit" in a special five-hour commissioners meeting, during which he got into a shouting match with the county attorney and told Holmes she should resign because it was "disgusting how you fight the people." She left the meeting in tears.

Holmes has grown so disheartened by the couple's oft-repeated allegations that she has stopped coming to meetings unless asked for. "I was to the point that, 'You guys aren't even telling half-truths anymore,' " she recalled. "It's all falsehoods and speculation. I'm not going to sit and argue with that."

In the end, the commissioners voted to sue the secretary of state's office for forcing them to certify the primary results. Their county attorney, R.B. Nichols, advised that the "frivolous lawsuit" would "not pass muster" in court and would cost the county more than $100,000.

That day, Democrats on the House Oversight Committee released their report into the threat of election misinformation. It singled out "fraudulent" audits in Maricopa County, Ariz., and Otero County as key drivers in an effort by "malicious domestic actors" to erode trust in American democracy.

At the meeting at the Nebraska senior center in early August, Clements appealed to his audience to get on social media and to keep showing up at county commission meetings, again and again, until local leaders are worn down and give in. All they need to do to change the system, he assured them, is to win over a handful of commission votes.

"We're in a contest of wills. Who is going to break whose will?" Clements said. "I'm not asking you all to storm the beaches of Normandy, to suffer a bloody death to save our republic. I'm asking you all to consider showing up to an air-conditioned building, organizing, opening your mouth and saying: 'These machines suck. I know they do. I don't want them. Make them go away.' "

One woman told him she and others in her county were planning to have a days-long outdoor slumber party near her county's one ballot drop-box before the November election to guard it from being stuffed with ballots - a fear propagated by the debunked film 2000 Mules.

A rancher named Dave Wright raised his hand to say that it was obvious to him the Democratic National Committee had figured out how to cheat, so why couldn't the Republicans do so as well?

Clements ended on a mournful note just before the audience began trickling out into the quiet evening, the sun setting over fields of thirsty corn.

"I stand before you as someone who used to be an award-winning professor, an award-winning prosecutor - who is unemployed," Clements said. "I come to you as someone who had a future. And if we don't fix our country, I can't go back to that world."

The Washington Post's Magda Jean-Louis and Alice Crites contributed to this report.