The U.S. Supreme Court on Monday brought certainty to a primary period muddled by confusing and diverging state-level rulings, ruling unanimously that the 14th Amendment did not allow states to overturn former President Donald J. Trump.
But the reaction to the ruling showed that challenges to Mr. Trump’s candidacy had hardened political lines and angered Republicans who saw the lawsuits as an undemocratic attempt to meddle in the election. And the decision came as voters in more than a dozen states prepared for Super Tuesday primaries.
“It got people involved,” said Brad Wan, the GOP caucus coordinator in Colorado, the first of three states to expel Mr. Trump, and the state at the center of the Supreme Court case. “They feel that the Democrats in this state are trying to take away basic rights. People are speaking out in coffee shops, in churches, saying we can’t allow this to happen.”
The ballot challenges, filed in more than 30 states, focused on whether Mr. Trump’s efforts to overturn his 2020 election loss disqualified him from re-election. The cases were based on a clause in the 14th Amendment, enacted after the Civil War, that bars government officials who were “engaged in rebellion or insurrection” from holding office.
On Monday, all nine Supreme Court justices agreed that individual states could not ban presidential candidates under the sedition provision. Four judges would have left it at that. A five-justice majority, in an unsigned opinion, went on to say that Congress must act to give effect to this section.
In Illinois, where the Supreme Court ruling overruled a state judge’s finding last week that Mr. Trump was ineligible, many voters said Mr. Trump belonged on the ballot.
The former president had remained on the ballot in the three states to disqualify him — Colorado, Illinois and Maine — while he appealed those decisions. The opinion of the Supreme Court gave a final decision.
“People are rallying him as hard as they can,” said Herbert Polchow, 67, a Republican retiree in Rankin, Ireland, who said the challenges at the polls were just a way for Democrats to prevent Mr. Trump from becoming chairman.
Zachary Spence, 42, of Danville, Ill., said the Supreme Court decision was a victory for voters.
“You can’t take away people’s choice,” said Mr. Spence, a supporter of the former president.
In Colorado, Patrick Anderson said he had voted for Mr. Trump twice but would not do so a third time because of Mr. Trump’s denial of the results of the 2020 election. He said he agreed with the Supreme Court, as a point.
“I think the presumption should be to let the voter have his say,” Mr. Anderson, 77, said. “But I don’t think there should be a popularity contest if there’s crime.”
While Republican officials were united in opposing the ballot challenges, the question had divided Democrats, some of whom questioned the political and legal merits of challenging Mr. Trump.
Even for those who supported the ballot challenges, Monday’s decision brought clarity after weeks of uncertainty.
“I believe Colorado should be able to ban oath-breaking insurgents from our presidential ballot, but the US Supreme Court disagrees,” said Colorado Secretary of State Jenna Griswold, a Democrat. “Thus, according to this, Donald Trump is an eligible candidate and the votes for him will be counted in the state of Colorado.”
Shenna Bellows, Maine’s Democratic secretary of state, who ruled in December that Mr. Trump was ineligible to appear on the state’s primary ballot, issued an updated ruling on Monday that mirrored the Supreme Court ruling. “Consistent with my oath of office and my obligation to follow the law and the Constitution,” he wrote, “I hereby withdraw my determination that Mr. Trump’s primary petition is invalid.”
The new certainty, officials on both sides of the issue agreed, was important. The Colorado and Maine primaries are Tuesday, and the Illinois primary is March 19.
“Now that this decision has been made, voters in Super Tuesday states can go to the polls without any additional distractions on this issue,” said Republican Secretary of State Wes Allen of Alabama.
Those who led efforts to remove Mr. Trump from the ballot expressed their disappointment and stood by their decision to bring the challenges.
Ben Clements, the president of Free Speech for People, a group that filed several state-level appeals, called the Supreme Court’s decision “a great disservice to the country and our constitutional democracy.” He said in an interview that the attempt to impeach Mr. Trump “was absolutely a fight worth fighting.”
Some voters agreed. Richard Uttman, 69, an independent politician from Palermo, Maine, said he was disappointed with the court’s decision and that “the ruling shows that the Constitution has been violated.”
“He’s a criminal,” Mr. Utman said. “He has no business position. He has no business being president.”
John Anthony Castro, a longtime Republican presidential candidate who has filed federal lawsuits challenging Mr. Trump’s eligibility in more than 20 states, said he did not believe the Supreme Court’s opinion prevented him from continuing his legal cases. None of Mr. Castro’s lawsuits have been successful, and many have been dismissed or withdrawn.
Many Republicans used dire language to describe the challenges to Mr. Trump, and some spoke ominously of what might have happened if the Supreme Court had ruled otherwise.
Jay Ashcroft, Missouri’s secretary of state, previously said conservative states could try to overturn President Biden if the Supreme Court allowed Mr. Trump to be removed from the ballot.
“I’m grateful that the Supreme Court put an end to this stupid attempt to subvert our election process,” said Mr. Ashcroft, a Republican.
Sen. Deb Fischer, R-Nebraska, said “Americans can celebrate that the Supreme Court rejected this authoritarian effort to interfere in our elections and prevent Donald Trump from even running for office.”
Iowa Gov. Kim Reynolds, a Republican, praised the decision and accused Colorado of a “blatant attempt to subvert the will of the American people in the upcoming presidential election.”
Some voters who dislike Mr. Trump said they too agreed with the Supreme Court.
At an early voting site in Wheaton, Ill., a suburb of Chicago, Laura Edwards said she worried that the legal battle over Mr. Trump’s appearance on the ballot may have given him a political boost.
“It’s giving him more attention and he’s going to use it as a victory,” said Ms. Edwards, 42, who voted in the Democratic primary. “They should have left him on the ballot and let us hope that reasonable people don’t vote for him.”
Karl Klockars, 78, a lawyer from Wheaton who voted early for a candidate other than Mr. Trump in the Republican primary, said the Supreme Court “did the right thing and it’s obvious from the fact that there were no dissenters.”
And Danville retiree Gregory Hinotte, 64, said he didn’t usually vote in primaries, but this time he did because he believed voting was the best way to prevent Mr. Trump from becoming president again.
“Voting is the way,” said Mr. Hinote, who chose a Democratic primary ballot. “I think we should vote and vote for him. That’s the way to do it — not ban it from state to state.”
Robert Chiarito reported from Wheaton, Ill., Farah Anderson from Danville, Ill., Dave Phillips from Colorado Springs and Mitch Smith from Chicago. The report was made by Maggie Astor, Murray Carpenter, Adam Liptak and Jenna Russell.