The former president has called such efforts 'election interference.'
Citizens for Responsibility and Ethics (CREW), a Washington-based watchdog group, on Wednesday filed a lawsuit on behalf of a handful of voters seeking to bar former President Donald Trump from the 2024 ballot in Colorado under Section 3 of the 14th Amendment based on his alleged involvement in the Jan. 6 attack on the U.S. Capitol.
The suit -- quickly dismissed by Trump's team -- marks one of the first serious challenges to his qualifications as a presidential candidate based on a 14th Amendment argument.
Section 3 states that someone isn't eligible for future office if, while they were previously in office, they took an oath to support the Constitution but then "engaged in insurrection or rebellion against the same, or [gave] aid or comfort to the enemies thereof," unless they are granted amnesty by a two-thirds vote of Congress.
Supporters of this theory argue this applies to Trump because of his conduct after he lost the 2020 election but sought to reverse the results. Previous such efforts focused on other Republicans have failed, but CREW last year successfully pushed to remove a county official in New Mexico who was convicted of trespassing in connection with the attack on the Capitol.
Wednesday's suit against Trump was filed, with CREW's attorneys, by six Republican and unaffiliated Colorado voters, including former state, federal and local officials.
The suit accuses Trump of inciting and aiding the mob that stormed the Capitol two years ago. He was previously impeached by the House of Representatives for the same but was acquitted by the Senate and has repeatedly maintained he did not incite the rioters.
CREW President Noah Bookbinder said that the organization is bringing the lawsuit because "it is necessary to defend our republic both today and in the future."
Trump has denied all wrongdoing and called the efforts to disqualify him under the 14th Amendment "election interference."
A Trump campaign spokesman, Steven Cheung, blasted the new suit in a statement to ABC News.
"The people who are pursuing this absurd conspiracy theory and political attack on President Trump are stretching the law beyond recognition," Cheung said, in part, adding, "There is no legal basis for this effort except in the minds of those who are pushing it."
A broader campaign is emerging to keep Trump from the ballot next year because of the 14th Amendment.
John Anthony Castro -- who is running for the GOP presidential nomination as a write-in candidate -- filed and has docketed 14th Amendment cases in Arizona, Georgia, Michigan, New Hampshire, Pennsylvania and Wisconsin. Castro has also mailed federal lawsuits to the district court clerks in Idaho, Kansas, Montana, North Carolina, Oklahoma, South Carolina, Utah, West Virginia and Wyoming.
Sen. Tim Kaine, D-Va., acknowledged the brewing battle during an appearance Sunday on ABC's "This Week."
"My sense is it's probably going to get resolved in the courts," he said.
Colorado Secretary of State Jena Griswold, a Democrat, said in her own statement that "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."
A news release from Griswold's office also outlined their view of how Colorado law is unclear on how to consider the requirements of the U.S. Constitution in determining a candidate's eligibility.
Currently, no candidates have qualified for the presidential primary ballot in Colorado, according to Griswold's office.
Griswold, in her role as the state's chief elections official, is named as the defendant in the CREW lawsuit along with Trump.