The U.S. Supreme Court on Friday agreed to hear Donald Trump’s appeal of a judicial decision barring the former president from Colorado’s Republican primary ballot, taking up a politically explosive case with major implications for the 2024 presidential election.

At issue is the Colorado Supreme Court’s Dec. 19 ruling disqualifying Trump from the state’s primary ballot based on language in the U.S. Constitution’s 14th Amendment for engaging in insurrection, involving the Jan. 6, 2021, attack by his supporters on the U.S. Capitol.The justices took up the case with unusual speed. Trump, the frontrunner for his party’s nomination to challenge Democratic President Joe Biden in the Nov. 5 U.S. election, filed his appeal on Wednesday. The justices indicated they would fast-track a decision, scheduling oral arguments for Feb. 8. The Colorado Republican primary is scheduled for March 5.

The state court, acting in a challenge to Trump by Republican and unaffiliated voters in Colorado, found him ineligible for the presidency under a constitutional provision that bars anyone who “engaged in insurrection or rebellion” from holding public office, barring him from the primary ballot. The U.S. Supreme Court did not act on a separate appeal of the state court’s decision by the Colorado Republican Party.

The Colorado case thrusts the Supreme Court – whose 6-3 conservative majority includes three justices appointed by Trump – into the unprecedented and politically fraught effort by his detractors to invalidate his campaign to reclaim the White House.

Trump’s spokesperson Steven Cheung praised the court’s decision to hear the case, characterizing the disqualification efforts as “part of a well-funded effort by left-wing political activists hell-bent on stopping the lawful re-election of President Trump this November, even if it means disenfranchising voters.” Colorado Secretary of State Jena Griswold said people in her state and around the United States “deserve clarity on whether someone who engaged in insurrection may run for the country’s highest office.”

Noah Bookbinder, president of Citizens for Responsibility and Ethics in Washington, a watchdog group representing the challengers to Trump, added, “We’re glad that the Supreme Court will definitively decide whether Donald Trump can be on the ballot. We look forward to presenting our case and ensuring the Constitution is upheld.”

Many Republicans have decried the disqualification drive as election interference, while proponents of disqualification have said holding Trump constitutionally accountable for an insurrection supports democratic values. Trump faces criminal charges in two cases related to his efforts to overturn his 2020 loss to Biden.

Trump also has appealed to a Maine state court a decision by that state’s top election official barring him from the primary ballot under the same constitutional provision at issue in Colorado.