Money is pouring into the Democratic primary to represent Denver in Congress as Rep. Diana DeGette faces her most potent challenge in decades.
The campaigns and outside groups have spent millions. Meanwhile, online prediction markets shifted dramatically this week: After leftists and progressives notched victories in New York, speculators are betting that challenger Melat Kiros will unseat DeGette, a 29-year incumbent.
DeGette’s campaign and supporters are spending the most heavily, a total of more than $2 million as of mid-June to boost the incumbent and attack Kiros.
Meanwhile, Kiros’ campaign has gained momentum — including an endorsement from U.S. Sen. Bernie Sanders — and her supporters claim she’s pulled ahead in polling. A Democratic Socialist, she notched an early victory by winning the top spot on the ballot. Her campaign and outside groups have spent more than $1 million.
The heavy spending may show the race is tightening.
Justice Democrats, which supports Kiros, released a poll claiming she was ahead 41% to DeGette’s 36%. The poll of 307 likely voters was conducted by Data for Progress and claimed a 6-point margin of error.
Only one other poll has been released, a March survey by the same group. That earlier survey had Kiros at just 7% support — representing a 34-point swing for Kiros, if the polls are accurate.
It all adds up to an uncertain race that’s drawing a lot of attention. Prediction markets like Kalshi, where users put their money on expected outcomes, have swung wildly. Users’ consensus has swung back and forth between Kiros and DeGette — with expectations for Kiros spiking on Wednesday after the New York results.
In all, users on Kalshi and Polymarket have spent nearly $350,000 on the race as of Thursday.
Millions in spending
Groups supporting DeGette have spent more than $1.3 million on ads slamming Kiros and supporting DeGette, in addition to hundreds of thousands from the campaign itself.
One group, Mile High Accountability Project, spent $350,000 on a 30-second ad on YouTube and social media claiming that Kiros wants to divide Democrats. The ad also claims that President Donald Trump loves Democrats like Kiros.
A representative for the PAC, which formed April 29, didn’t respond to a request for comment. The group hasn’t disclosed any of its donors and won’t be required to do so until July, Newsline reported.
The ad claimed Kiros “recently moved to Denver,” even though she and her family immigrated to Denver when she was 11 months old. The ad has faced criticism online for its xenophobic implication that Kiros is a foreigner unfit for office.
Another ad from Project 218 repeated the claims about Kiros being a recent transplant, and echoed DeGette’s allegation that Kiros wants to leave NATO — which Kiros also denies. The National Association of Realtors Political Action Committee is also supporting DeGette and has spent $11,000 on digital ads, among other items, according to campaign finance records.
An official DeGette mailer depicts Kiros in a space suit and says that her views are “out there.” Another DeGette campaign mailer claims that Kiros’ record is “paper thin” and that she’s only voted in Denver once in her life.
According to VoteRef, Kiros voted in the 2025 Denver County Coordinated Election and previously voted in seven elections in neighboring Arapahoe County dating back to 2016.
In response, Kiros slammed DeGette’s record and her support from PACs. “She takes money from the real estate lobby while voters in Denver are priced out of the neighborhoods they grew up in. If that's a thick resume, I'll take thin,” Kiros said in a written statement to Denverite. Meanwhile, the Justice Democrats PAC has spent roughly $450,000 in support of Kiros.
DeGette entered the final stretch with a strong financial advantage. She had raised $1.4 million as of June 10 and had $459,000 in cash for the last three weeks of the election.
Kiros, meanwhile, had raised about $660,000 and had about $88,000 for the final sprint. Those figures exclude outside groups.
The current numbers don’t show the full picture. Campaigns don’t have to submit their full campaign finances, including complete details about donors, until July 15.
Endorsements
DeGette and Kiros have collected a slew of endorsements.
In addition to Sen. Sanders, Kiros has also been endorsed by the Sunrise Movement, a group of environmental activists, and the Colorado Working Families Party.
DeGette has been endorsed by the Congressional Progressive Caucus PAC and various unions like the Colorado Professional Firefighters.
James has been endorsed by former mayor Wellington Webb and former state Rep. Wilma Webb, and the Collective PAC, which advocates for representation of Black communities in government.
Kevin J. Beaty contributed to this article.
