Four Republican and two unaffiliated voters filed suit in state court in Denver on Wednesday seeking to block the secretary of state from placing Donald Trump on any future primary or general election ballot in Colorado.

A Trump spokesman did not immediately respond to a request for comment on the suit.

The lawsuit contains prominent political names on the plaintiffs’ side, including former Republican Senate Majority Leader Norma Anderson and Denver Post columnist Krista Kafer among those challenging Trump’s eligibility for the ballot. Former Republican legislative candidate Mario Nicolais, former solicitor general Eric Olson and the watchdog group Citizens for Responsibility and Ethics in Washington are part of the legal team that brought the suit.

“Four years after taking an oath to ‘preserve, protect and defend’ the Constitution,” the 115-page lawsuit alleges, “Trump tried to overthrow the results of the 2020 election, leading to a violent insurrection at the United States Capitol to stop the lawful transfer of power to his successor. By instigating this unprecedented assault on the American constitutional order, Trump violated his oath.”

The plaintiffs have grounded their claims in state law and in the 14th Amendment’s prohibition on certain state and federal officials ever holding federal office if they “shall have engaged in insurrection or rebellion.”

The extraordinary move to bar a presidential candidate from the ballot – as that candidate is also facing multiple criminal charges – relies on a recent case in New Mexico, in which courts removed a local elected official from his position due to his involvement in the Jan. 6 attack on the Capitol.

In a statement, Secretary of State Jena Griswold, a Democrat, said she is “hopeful that this case will provide guidance to election officials on Trump’s eligibility as a candidate for office.”

Among the Republican plaintiffs are former U.S. Rep. Claudine Cmarada, who represented Rhode Island in Congress and lives in Colorado, and Michelle Priola, the wife of state Sen. Kevin Priola, the Henderson Democrat who switched parties a year ago after winning election to his seat twice as a Republican. Anderson’s daughter-in-law, Pam Anderson, was the 2022 Republican nominee for Colorado secretary of state who lost to Griswold.

The Colorado GOP slammed the lawsuit on social media, declaring that “Never-Trumpers, RINO’s, & Democrats are colluding to block [Trump] from accessing the 2024 Colorado Republican Primary Ballot,” using a derisive acronym for “Republicans in name only.”

The state party went on to accuse Griswold of “likely invit[ing] the lawsuit so a judge could make the decision to block Trump instead of you doing it yourself.”

“Per Colorado Law, the Colorado Republican Party will decide who gets on the primary ballot not you or a leftwing judge,” the Colorado GOP added on X, the platform formerly known as Twitter.

In a fundraising email sent on Wednesday, state GOP chair Dave Williams said the party plans to “consider all options, whether litigation or otherwise, to preserve the right of Republican voters to vote for President Trump” or other Republican candidates on Colorado’s ballot.

Some groups have demanded that states’ top election officials bar Trump under the clause that prohibits those who “engaged in an insurrection or rebellion” against the Constitution from holding higher office. None has taken that step, looking for guidance from the courts on how to interpret a clause that has only been used a handful of times since the 1860s.

The lawsuit Wednesday was the first filed by an organization with significant legal resources. It may lead to similar challenges in other states, holding out the potential for conflicting rulings that would require the Supreme Court to settle.

The 14th Amendment, ratified in 1868, helped ensure civil rights for freed slaves – and eventually for all people in the U.S. But it also was used to prevent former Confederate officials from becoming members of Congress after the Civil War and taking over the government against which they had just rebelled.

The clause cited in the lawsuit allows Congress to lift the ban, which it did in 1872 as the political will to continue to bar former Confederates dwindled. The provision was almost never used after that.

The clause cites “presidential electors” – but not presidents themselves – as being disqualified if they previously swore an oath to uphold the Constitution and then broke it.

The 14th Amendment was used last year to bar from office a New Mexico county commissioner who entered the U.S. Capitol on Jan. 6. That was the first time it was used in 100 years. In 1919, Congress refused to seat a socialist, contending he gave aid and comfort to the country’s enemies during World War I.

In its complaint, Citizens for Responsibility and Ethics in Washington asked the court to expedite the matter so it can be resolved before Colorado’s primary ballot is set. Colorado is scheduled to hold its presidential primary on March 5, 2024. State law sets a deadline of Jan. 5, 2024, for the secretary of state to certify the ballot.

The case is Anderson et al. v. Griswold et al.

Nicholas Riccardi of the Associated Press contributed to this article.