Just over six weeks before primary ballots go in the mail to Colorado voters, the candidate rosters are nearly set — teeing up a half dozen congressional primaries spread across the state’s three open, Republican-held seats and its lone toss-up district, where a Democrat is the incumbent.

It’s been at least 100 years since voters in three of Colorado’s congressional districts were faced with choosing new representation at this point in the election cycle, and it took a head-spinning series of unprecedented decisions by all three of the state’s Republican House members to get here.

First, Ken Buck announced last fall that he wasn’t seeking reelection to a sixth term in the deep red 4th Congressional District, which covers Douglas County, Loveland and the Eastern Plains.

Then just before the end of last year Lauren Boebert announced she was moving into Buck’s district to run for a third term, rather than risk losing to the Democrat who came within a whisker of beating her last election in the sprawling 3rd Congressional District, covering the Western Slope and Southern Colorado.

A few days later, Doug Lamborn declared that his current, ninth term in the El Paso County-based 5th Congressional District would be his last, freeing up the only seat in the state that has never been represented by a Democrat.

Capping a string of surprising turns, Buck — a former chairman of the state GOP, who spent much of the previous year at loggerheads with his fellow Republicans — threw another loop into the mix in March when he did something no U.S. House member from Colorado had ever done before by resigning in the middle of his term.

That triggered a special election to fill the remainder of Buck’s term, which under state law had to be scheduled on one of two Tuesdays in late June — one of which, not coincidentally, happens to be the date of this year’s primary election, June 25.

While holding the two elections at the same time — and, it turns out, on the same ballot — will save election officials plenty of money, Boebert accused Buck of timing his resignation to impair her candidacy, though Buck denies her charges.

Due to a set of rules that govern the state’s election schedules — and the Republicans’ razor-thin majority in the House of Representatives— Boebert decided against running in the special election for Buck’s seat, since if she won, she’d have to resign the seat she currently occupies, and it would have to remain vacant for the rest of the year. That meant that one of her many primary rivals might appear on the ballot twice — once as the GOP nominee in the special election and a second time in the Republican primary — potentially giving that candidate a leg up.

But delegates to a special convention held at the end of March declined to give any of the other Republicans already running for the seat an advantage, instead nominating a self-described “placeholder” candidate, Greg Lopez, a former Parker mayor with two unsuccessful runs for governor under his belt.

The Democrats went a different direction, sending first-time candidate Trisha Calvarese, one of their party’s primary contenders, to the special election ballot.

In another wrinkle — in an election season that has had more than its share of them — Calvarese must first survive a lawsuit challenging her eligibility to run. Filed last week by a voter whose lawyers represent former President Donald Trump in another Colorado case, the lawsuit alleges Calvarese hasn’t been a registered as a Democrat in the state long enough to meet statutory and party requirements. Calvarese, who grew up in Colorado and moved back last fall to help provide home hospice care for her parents, maintains she’s eligible and filed this week to intervene in the case.

The case is expected to be resolved before Colorado Secretary of State Jena Griswold has to certify the special election and primary ballots on April 29.

By then, it will be clear whether GOP primaries in two of the state’s open congressional districts — both with long histories of electing Republicans — will set records for the number of candidates to appear on a Colorado ballot for federal office.

One of those races — in the 3rd CD, Boebert’s old district — is tied for the most candidates in a congressional primary, at six, while the other, in Buck’s former 4th CD, counts five Republicans on the ballot. A couple of GOP candidates in the 4th CD are awaiting rulings on their petitions and could yet boost that total.

The previous record-holder for the state’s most crowded congressional primary ballot was the race for the GOP nomination in 2006, when Lamborn was one of six Republicans running to replace retiring Republican Joel Hefley in the heavily Republican 5th CD. Lamborn won a plurality with just 27% of the vote, edging out second-place finisher Jeff Crank, a Hefley aide, by fewer than 1,000 votes. Crank, notably, is making another run for the seat this year.

Congressional candidates can qualify for primaries in Colorado three ways: by winning support from at least 30% of the delegates to their party’s district assembly, by turning in at least 1,500 valid petition signatures from fellow party members who reside in their district, or by going a hybrid route that involves clearing 10% of the delegate vote while meeting the same signature requirement.

The latter, hybrid method used to make more sense when Colorado’s primaries were held later in the year — as recently as a few decades ago, primaries took place in early September — so candidates who fell short of qualifying at assembly but received at least 10% support could turn around and mount petition drives. But ever since the state’s primary election moved to late June, the deadline to turn in petitions precedes most party assemblies, which are held in March and early April.

This year, petitions were due on March 19. The only candidates whose petitions haven’t yet been finalized turned theirs in on the last possible day.

As of April 19, here’s the lineup in the six primary races for Colorado’s U.S. House seats:

The six Republicans running in the 3rd CD are State Board of Education member Stephen Varela, who won top-line on the ballot by winning the most delegate votes at the assembly; former state Rep. Ron Hanks, R-Cañon City, who ran unsuccessfully for the U.S. Senate last cycle and moved into the 3rd CD in January after Boebert moved out; Grand Junction attorney Jeff Hurd, who had been challenging Boebert in the primary before she jumped districts; and, a trio of first-time candidates who are largely self-funding their campaigns: Curtis McCrackin, Russ Andrews and Lew Webb.

The winner will face Democrat Adam Frisch, the former Aspen City Council member who came within fewer than 600 votes of unseating Boebert in 2022 and has raised more than $12 million this cycle, shattering records for Colorado congressional candidates.

In the 4th CD Republican primary, Boebert landed top-line designation at the assembly after already qualifying by petition. She’s one of five candidates in a field that could grow, including parents rights advocate Deborah Flora, state Reps. Mike Lynch of Wellington and Richard Holtorf of Akron; and former state Sen. Jerry Sonnenberg, a Logan County commissioner from Sterling. Two more GOP candidates are hoping to make the ballot by petition: Chris Phelen and Peter Yu.

There’s a primary on the Democratic side in the 4th CD, too, featuring Calvarese on the top-line, along with Marine veteran Ike McCorkle — who challenged Buck twice unsuccessfully — and engineer and addition recovery advocate John Padora.

Both Republicans running in the 5th CD lost primaries to Lamborn over the years — Crank, in 2006 and 2008, when he sought a rematch, and primary top-liner Dave Williams, the chairman of the Colorado GOP and a former state lawmaker, who finished behind Lamborn in a four-way primary two years ago.

There’s a Democratic primary for the 5th CD seat, too, this year, between scientist and astronomy teacher River Gassen, the top-liner at the party’s assembly, and Army veteran and veteran’s advocate Joe Reagan, both first-time candidates.

Democratic incumbent Yadira Caraveo is defending the state’s nearly evenly divided 8th Congressional District — covering portions of Adams, Larimer and Weld counties north of the Denver metro area — against the winner of a GOP primary between state Rep. Gabe Evans of Fort Lupton, who secured top line on the ballot, and former state Rep. Janak Joshi, who moved into the district from Colorado Springs earlier this year.

Editor’s note: This column was updated on April 19, 2024, to reflect Lew Granado’s and Floyd Trujillo’s failure to qualify by petition for the Republican primaries in Colorado’s 3rd and 4th congressional districts, respectively.

Ernest Luning has covered politics for Colorado Politics and its predecessor publication, The Colorado Statesman, since 2009. He’s analyzed the exploits, foibles and history of state campaigns and politicians since 2018 in the weekly Trail Mix column.

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