Colorado GOP Fails to Block Unaffiliated Voters From Primaries

The Colorado Republican Party requested an emergency order from a federal judge to prevent unaffiliated voters from participating in the party's June 30, 2026, primary election. The motion followed a March 31 ruling by U.S. District Court Judge Philip A. Brimmer, who declared that Colorado's 75% supermajority requirement for a party's central committee to opt out of semi-open primaries is unconstitutional.

Republican leaders argued that because the legal deadline to opt out had passed on October 1, 2025, the timing of the court's ruling left the party with no other way to prevent what they termed irreparable constitutional injury. The party clarified that this specific request was a time-limited remedy for the 2026 cycle rather than an attempt to invalidate Proposition 108 entirely.

Colorado Secretary of State Jena Griswold opposed the motion, arguing that the request contradicts state law and would cause administrative chaos shortly before ballots are mailed. Judge Brimmer initially rejected the filing on technical grounds due to its length, forcing the party to refile. In previous assessments of the case, Brimmer noted there was no evidence that unaffiliated voters had caused harmful effects to the party's election outcomes.