A group of Colorado voters filed suit Wednesday to keep former President Donald Trump off the state’s 2024 presidential ballot in the nation’s first major challenge to be backed by significant legal resources.

The ballot-qualification petition, which involves a national liberal group, names the Republican front-runner and Colorado Secretary of State Jena Griswold as defendants. It argues that Trump is barred from seeking or holding office based on the events on and around the Jan. 6, 2021, attack on the U.S. Capitol. The plaintiffs are all Republican or unaffiliated voters, including some former officeholders.

The lawsuit, filed in Denver District Court, cites Section 3 of the 14th Amendment, the Civil War-era federal constitutional amendment, which bars people from holding office if they have “engaged in insurrection or rebellion” against the country.

“(Trump) knowingly sought to subvert our Constitution and system of elections through a sustained campaign of lies,” the legal petition states. “His efforts culminated on January 6, 2021, when he incited, exacerbated, and otherwise engaged in a violent insurrection at the United States Capitol by a mob who believed they were following his orders, and refused to protect the Capitol or call off the mob for nearly three hours as the attack unfolded.”

While a few fringe figures have filed thinly written lawsuits in a few states citing the 14th Amendment, Wednesday’s lawsuit may lead to similar challenges in other states. That holds out the potential for conflicting rulings that would require the U.S. Supreme Court to get involved.

Plaintiff’s attorney Mario Nicolais, a managing partner at Lakewood firm KBN Law, said the Colorado complaint faces an inherent timeline crunch — the state’s presidential primary ballots need to be certified in January.

If the Denver court decides his clients’ way, he assumes the ruling will face appeals, possibly all the way to the Supreme Court.

“It’s our position that this is a rule-of-law case, not a partisan case,” said Nicolais, who previously ran for office as a Republican. “That’s why we filed it. No one is above the law, including former President Trump. In this case, the Constitution is very clear.”

Nicolais worked on the case with other attorneys and with Citizens for Responsibility and Ethics in Washington (CREW), a liberal watchdog group.

In a statement, Trump campaign spokesperson Steven Cheung accused the plaintiffs of pursuing an “absurd conspiracy theory” and “stretching the law beyond recognition much like the political prosecutors in New York, Georgia and D.C.” Trump faces a myriad of criminal and civil cases, including around the 2020 presidential election, in those jurisdictions.

“There is no legal basis for this effort except in the minds of those who are pushing it,” Cheung said.

Several of the lawsuit’s petitioners are Republicans: Claudine Cmarada, a former Rhode Island congresswoman, then known as Claudine Schneider, who now lives in Colorado; Norma Anderson, a former majority leader in both the Colorado state House and Senate; Denver Post columnist Krista Kafer; and Michelle Priola, who changed to unaffiliated in August 2022 but switched back to Republican on Aug. 22, according to state voter records. She has been active in Republican politics and is married to Republican-turned-Democratic state Sen. Kevin Priola.

Another plaintiff, Republican-turned-unaffiliated voter Chris Castilian, served as deputy chief of staff for Colorado’s last GOP governor, Bill Owens. Former Loveland City Council member Kathi Wright, an unaffiliated voter, also joined the suit. None of the voters involved are current Democrats.

CREW previously worked with New Mexico residents who successfully sued to remove a county commissioner there and disqualify him from future office.

The commissioner, Couy Griffin, had previously been found guilty of a misdemeanor in federal court for entering the U.S. Capitol’s grounds on Jan. 6, 2021, but without going inside the building. New Mexico state court Judge Francis Mathew wrote that Griffin had “aided the insurrection” — keywords for the Colorado lawsuit.

“The Constitution’s qualifications are not optional,” CREW President Noah Bookbinder said Wednesday in a call with reporters. “They are the supreme law of the land and they are the cornerstones of our democracy. This qualification in particular was intended to safeguard democracy. It ensures those who attacked our democracy — that those who attacked our democratic system of government by engaging in insurrection — not be put in charge of it.”

Bookbinder said the group selected Colorado for the lawsuit because the state’s laws allow voters to file this type of ballot challenge and allow adjudication relatively early in the election process. CREW believes the plaintiffs have standing as Republicans traditionally able to cast ballots in the state’s primary or under changes allowing unaffiliated voters to participate, too.

“Republican primary voters deserve to know whether a leading candidate is eligible to serve in the office that they’re seeking, so we hope that this case will go a long way towards answering that question in a court of law,” CREW attorney Donald Sherman said.

Sherman said CREW worked with plaintiffs because they all have solid “Republican bona fides,” a willingness to step forward despite the withering attacks some Trump critics have faced and a demonstrated commitment to public service in some way. He singled out Anderson, who spent nearly two decades in the State Capitol and has a preschool named after her.

Colorado Republican Party Chairman Dave Williams pledged in a fundraising email Wednesday afternoon to “consider all options, whether litigation or otherwise” to keep Trump on the ballot for the March primary. He accused Democrats of trying “to weaponize our judicial system” and called the plaintiffs “desperate ‘Never-Trump’ activists.”

“These despicable malcontents shouldn’t get away with robbing you of your options or vote,” Williams wrote in the email. “They know they can’t win in the court of public opinion so now they are hoping a leftwing activist judge will let them win by abusing a court of law.”

Griswold, a Democrat, was named in the petition because her office supervises elections and certifies the statewide ballot.

“I look forward to the Colorado court’s substantive resolution of the issues,” Griswold said in a statement, “and am hopeful that this case will provide guidance to election officials on Trump’s eligibility as a candidate for office.”

The Associated Press contributed to this story.

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