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Former President Donald Trump steps off his plane as he arrives at Hartsfield-Jackson Atlanta International Airport on Thursday, August 24, 2023.
Washington CNN  — 

A Washington-based advocacy group filed a lawsuit on Wednesday to block former President Donald Trump from the 2024 Republican primary ballot in Colorado, citing the 14th Amendment’s ban on insurrectionists holding public office.

In recent weeks, a growing number of liberal and conservative legal scholars have embraced the longshot legal strategy. The lawsuit, from Citizens for Responsibility and Ethics in Washington, is the first high-profile legal case attempting to use the 14th Amendment to derail Trump’s presidential campaign.

Trump has denied wrongdoing regarding the January 6, 2021, attack on the US Capitol and said in a recent social media post that there is “no legal basis” to use the 14th Amendment to remove him from the ballot.

A post-Civil War provision of the 14th Amendment says any American official who takes an oath to uphold the US Constitution is disqualified from holding any future office if they “engaged in insurrection or rebellion” or if they have “given aid or comfort” to insurrectionists.

However, the Constitution does not spell out how to enforce this ban and it has only been applied twice since the late 1800s, when it was used extensively against former Confederates.

The lawsuit was filed by CREW on behalf of six Colorado voters, which the group says are independents or Republicans, including former US Rep. Claudine Schneider and former Colorado Senate Majority Leader Norma Anderson, both Republicans.

Noah Bookbinder, president of CREW, told CNN’s Abby Phillip on “NewsNight” Wednesday that the group chose Colorado because of its “courageous plaintiffs,” early position in the primaries and laws.

“For all of those reasons we thought it was a good first stop. It won’t be the last stop and we and others will bring other cases as well,” he said.

CREW was behind the most successful application of the so-called “disqualification clause.” A convicted January 6 rioter who was also an elected New Mexico county commissioner was removed from office last year on 14th Amendment grounds through a different but related legal mechanism that was initiated by CREW.

The nonprofit group on Wednesday sued Colorado Secretary of State Jena Griswold in state court and asked a judge to issue an order “declaring Trump disqualified under the Fourteenth Amendment” and barring Griswold “from taking any action that would allow him to access the ballot.”

“Because Trump swore an oath to ‘preserve, protect and defend’ the Constitution upon assuming the Office of the President on January 20, 2017 and then engaged in insurrection against the Constitution on and around January 6, 2021, he is disqualified under Section 3 of the Fourteenth Amendment from ‘hold[ing] any office … under the United States,’ including the Office of the President,” the lawsuit says.

Griswold, a Democrat, said in a statement that she believes Colorado state law is “unclear” on how to review constitutional requirements for “whether a candidate is eligible for office” and that the newly filed lawsuit will provide critical legal guidance.

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

The GOP primary in Colorado is on March 5, which is Super Tuesday. Trump’s federal criminal trial on charges stemming from his efforts to overturn the 2020 election is scheduled to begin March 4. He has pleaded not guilty.

In a statement after the lawsuit was filed, Trump campaign spokesman Steven Cheung said those promoting the 14th Amendment are “are stretching the law beyond recognition, much like the political prosecutors in New York, Georgia, and DC,” referring to Trump’s ongoing criminal indictments.

Trump has a commanding lead in the GOP primary race, according to recent polling.

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Legal scholars are split on how the 14th Amendment could be applied to Trump and how the ban would even be implemented, whether by election officials, Congress or a court given the constitutional ambiguities. Many expect the Supreme Court will ultimately weigh in on the matter in some fashion.

This story has been updated with additional information.

CNN’s Jack Forrest contributed to this report.