The Colorado GOP on Monday asked a federal judge to block unaffiliated voters from participating in the party’s primaries this year, a request that threatens to upend the June 30 election with ballots weeks away from starting to be mailed out.
The request piggybacks off a ruling late last month from U.S. District Court Judge Philip A. Brimmer, who found that a requirement in Colorado law that 75% of the party’s central committee must support opting out of the primaries before it can happen “constitutes a severe burden on the major parties’ right to association and is therefore unconstitutional.”
Randy Corporon and Alexander Haberbush, two lawyers for the Colorado GOP, wrote that since the party’s opt-out vote had to happen by Oct. 1, 2025, and Brimmer’s ruling wasn’t issued until March 31, unaffiliated voters should be blocked from participating in the Republican primaries “to prevent irreparable constitutional injury.”
County clerks must send ballots for the June 30 primary to military and overseas voters by May 16, the same day elections officials are required to provide a ballot to any voter who requests one in person at a county clerk’s office. Clerks can mail ballots to the rest of the electorate on May 29.
Unaffiliated voters, who now make up a majority of the state’s active, registered electorate, have been able to cast ballots in either the state’s Democratic or Republican primaries since 2018.
In 2016, voters passed Proposition 108, opening up the primaries to unaffiliateds. But a faction of Republicans has tried ever since to halt unaffiliated participation in GOP primaries, arguing that it dilutes the conservatism of their candidates.
The anti-Proposition 108 group of Republicans, led by former state Rep. Dave Williams, who was the Colorado GOP’s chairman for two years starting in March 2023, has repeatedly tried to persuade their party’s central committee to opt out of Colorado’s primaries. But they have failed year after year because they’ve been unable to meet the 75% threshold, most recently last year.
When the committee voted last year, 44.57% of the total central committee membership (507 people) voted to opt out.
But a majority of the Colorado GOP’s central committee, made up of a few hundred party loyalists, has supported opting out in many of the votes.
“The party does not seek with this emergency motion to invalidate Proposition 108 writ large or for future cycles,” Corporon and Haberbush wrote in their request for an emergency order. “The requested relief is strictly as-applied and time-limited to the 2026 primary election.”
Brimmer told the Colorado GOP that Corporon and Haberbush incorrectly filed their motion; it was too long. That will force the party to try again.
It’s unclear how long it will take for the request to play out in court.
The Colorado Secretary of State’s Office is the defendant in the case.
“The Republican Party’s request is not consistent with Colorado law and the will of Colorado voters,” Secretary of State Jena Griswold, a Democrat, said in a written statement. “It would create confusion for voters and election administration challenges weeks before ballots are sent for the June primary election. The court should deny it.”
The Colorado GOP doesn’t currently have a chair after Brita Horn resigned from the position April 17. That job is being filled in the interim by vice chair Eric Grossman.
The Colorado GOP filed its original challenge to Colorado’s law letting unaffiliated voters participate in partisan primaries in 2023.
This story previously appeared in the Colorado Sun.
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