Congressional candidate Eileen Laubacher, one of the Democrats seeking to challenge Republican U.S. Rep. Lauren Boebert, can participate in the party’s caucuses and assemblies pending a court hearing later this month, a Denver judge ruled Tuesday in response to a request filed by another Democrat running in Colorado’s 4th Congressional District.

Denver District Court Judge Mark T. Bailey declined to issue a temporary restraining order that would have blocked Laubacher from pursuing the Democratic nomination through the assembly process, which kicked off with precinct caucuses in some counties less than 20 minutes after the judge issued his decision.

Trisha Calvarese, one of Laubacher’s primary rivals, filed a lawsuit and asked for the restraining order late Monday, arguing that recent changes in party rules left Laubacher ineligible to aim for a spot on the June primary ballot by courting delegates to the Democrats’ congressional district assembly later this month.

The lawsuit alleges that Laubacher registered as a Democrat one day too late to meet new party restrictions added last fall that require candidates going through the assembly process to have been registered with the party for “twelve consecutive months.”

Calvarese and her co-plaintiff, Lisa Chollet, who has temporarily stepped down as the Democratic chair of the congressional district, argue that Colorado Democratic Party chair Shad Murib violated state statute when he “unilaterally” moved upcoming district assemblies back one day, from March 26 to March 27, in an effort to ensure that Laubacher met the requirements.

In an email to party officials over the weekend, Murib said his decision to push certain assemblies one day later was “an elegant solution” that made sure an “arbitrary” decision to schedule the Democrats’ 4th CD meeting one day earlier didn’t inadvertently disqualify a candidate from the process.

At issue is whether Murib has the ability to change district assembly dates or, as Calvarese and Chollet argue, that authority rests solely with the district chair.

Laubacher, a retired rear admiral and former top National Security Council staffer, changed her registration from unaffiliated to Democratic on March 27, 2025, shortly before declaring her candidacy in the heavily Republican district.

Calvarese, who ran unsuccessfully against Boebert two years ago, is seeking a rematch in a primary field that also includes John Padora and Jenna Preston.

Gauged by fundraising totals, Laubacher and Calvarese are the frontrunners in the primary. Laubacher reported raising $6.5 million in 2025 — more than twice as much as any of Colorado’s other congressional candidates and almost four times the $1.7 million raised by Calvarese.

Following an emergency hearing Tuesday afternoon, Bailey ruled that Calvarese and Chollet didn’t make a strong enough showing that “immediate and irreparable harm” would occur if he didn’t issue the order.

Noting that delegates headed to the district assembly aren’t bound to a particular candidate, the judge added that Calvarese could suffer if she comes in under the threshold required to get delegates at various stages of the process but “will maintain the ability to persuade all delegates notwithstanding the results of any county assembly.”

Andrew Nicla, a spokesman for the state Democratic Party, said in a statement that the judge “made the right decision today.”

“We look forward to a full hearing on the merits of this case, and we remain committed to a fair caucus and assembly process and open access to the ballot,” he said.

The case is scheduled to be heard in Bailey’s courtroom on March 16.

A spokeswoman for Calvarese told Colorado Politics that the state party was giving Laubacher “special treatment” by moving the district’s assembly date, noting that other congressional candidates have been barred from the assembly process under the party rule.

We believe in the integrity of elections and the rule of law,” said Fiona Boomer, Calvarese’s campaign manager, in a written statement. “Moving the assembly is admission that Laubacher was not previously eligible and now, to accommodate a lifelong Republican, the party is manipulating voter participation in assembly by changing the date to March 27th, the night before the state assembly. This lawsuit is about ensuring every Democratic voter has the opportunity to lend their voice to congressional candidate selection.”

In Colorado, major party candidates can qualify for the primary by getting the support of at least 30% of delegates to their party’s assembly, by submitting a sufficient number of valid petition signatures, or by taking both routes. Candidates who qualify by petition need only clear 10% delegate support at assembly, if they’re seeking the ballot by both methods.

In the 4th CD, Laubacher and Preston are circulating petitions and face a March 18 deadline to turn them in to the Colorado Secretary of State’s Office. It takes 1,500 signatures from members of the candidate’s party for congressional candidates to make the ballot.

In the email he sent to party officials, Murib argued that the party’s rules “are meant to enable participation, not restrict it.” He added, “A candidate who registered within the timeframe allowed by our rules shouldn’t be retroactively disqualified because of a logistical decision we made months later to hold the assembly on March 26 — especially when the DSP allows us to hold assemblies up to April 11, 2026.”

Calvarese said in a release announcing the lawsuit that Laubacher’s background as a registered Republican — before she disaffiliated and later became a Democrat — endangers her party’s chances of unseating Boebert.

“We will not win this district with an establishment-backed lifelong Republican,” Calvarese said. “We win by taking on the DC corruption, middlemen and monopolies driving up costs for families and buying politicians like Lauren Boebert. It’s critical that state party leaders enforce rules consistently, follow the law, and end the misguided favoritism toward establishment candidates.”

The 4th CD encompasses Douglas County and the Eastern Plains, as well as parts of Weld and Larimer counties on the Front Range. It’s the most solidly Republican congressional district in the state.