Ronald Fein, attorney for the petitioner, Free Speech for People, gives his ending rebuttal to his case before the Minnesota Supreme Court on Nov. 2, 2023. (Glen Stubbe, Star Tribune file/The Minnesota Star Tribune)

The next step for a Minnesota challenge to former President Donald Trump's 2024 ballot eligibility hinges on what the U.S. Supreme Court does with the Colorado high court's surprise decision to disqualify him.

The threshold question is if and when the U.S. Supreme Court decides to hear Trump's appeal of the Colorado ruling, according to John Bonifaz, president of the national nonprofit Free Speech for People. "If they do take it, stay tuned," he said.

Last fall, Free Speech for People filed a petition in Minnesota claiming that Trump's attempt to set aside the results of the 2020 election and his support for the Capitol riot on Jan. 6, 2021, disqualified him from holding future office.

In both Minnesota and Colorado, the challengers cited Section 3 of the 14th Amendment to the U.S. Constitution, commonly called the insurrection clause. The provision dates to the post-Civil War Reconstruction era and prohibits former officers from holding office again if they've "engaged in insurrection or rebellion" or "given aid or comfort" to those who did.

The Minnesota Supreme Court dismissed the challenge in early November. But on Tuesday, a slim majority of the Colorado Supreme Court said the clause prohibits Trump from being on the ballot next year. It was the first time in the nation's history that the clause had been effectively been invoked.

Trump is expected to appeal the Colorado ruling to the U.S. Supreme Court, which has the final word on constitutional issues.

In a statement late Tuesday, Trump legal spokeswoman Alina Habba said the decision "attacks the very heart of this nation's democracy. It will not stand, and we trust that the Supreme Court will reverse this unconstitutional order.''

The Colorado court embraced the theory put forward last summer by two Federalist Society members who are nationally renowned constitutional law professors, including Michael Stokes Paulsen of the University of St. Thomas Law School.

Paulsen co-authored the University of Pennsylvania Law Review article called "The Sweep and Force of Section 3." The 126-page article was an online sensation that has been downloaded more than 100,000 times.

Along with University of Chicago law Prof. William Baude, Paulsen argued Trump is ineligible for the 2024 ballot because of his attempt to set aside the results of the 2020 election won by President Joe Biden.

The Minnesota Supreme Court's decision didn't address the constitutionality of Trump being on the ballot.

Instead, the court said no Minnesota law prohibits a major political party from placing on the ballot or nominating "a candidate who is ineligible to hold office." The court then all but invited Free Speech for People to try again and raise the disqualification question for the general election.

Free Speech for People is waiting, for now, on the U.S. Supreme Court.

The ruling will be historically significant, potentially on par with the court's 5-4 decision in Bush v. Gore in 2000 that ended the ballot recount in Florida. That controversial decision, gave Florida's 25 electoral votes to Bush, sending him to the White House.

If the U.S. Supreme Court takes the case, decides it quickly and determines Trump is eligible to be on the 2024 ballot, that will settle the matter, Bonifaz said.

But if the high court upholds the Colorado ban, that would likely prompt ballot challenges in states across the country, he said.

Timing matters. If the court doesn't hear the case quickly, that would mean another ballot challenge to Trump in Minnesota, Bonifaz said.

"Once Minnesota moves into the general election stage, in our view, this matter will be ripe for re-challenging," he said.

Bonifaz said he believes the Minnesota Supreme Court's ruling was wrong in determining that partisan primaries are internal matters. He said previous U.S. Supreme Court rulings say that when parties use the election machinery of a state, they're engaging beyond internal affairs.

Alan Rozenshtein, constitutional law professor at the University of Minnesota, was succinct in his assessment of the Colorado decision.

"The main impact is that it is likely to lead to an authoritative [U.S.] Supreme Court decision, which will resolve the Minnesota case without the Minnesota Supreme Court having to rule, which is what I suspect the Minnesota court desperately wanted to begin with," he said.

Colorado officials say the issue there must be settled by Jan. 5, their deadline for printing presidential primary ballots.