Colorado Primaries: Socialist Wins, Bennet Governor Bid Ends
Colorado’s primary elections on June 30 delivered seismic results with national implications, as a democratic socialist candidate ousted a 15-term incumbent and a sitting U.S. senator saw his gubernatorial ambitions come to an end. The outcomes signal a deepening anti-establishment wave within the Democratic Party, fueled by voter frustration with the party’s ability to counter President Donald Trump’s agenda.
The Kiros Upset
Melat Kiros, a 29-year-old democratic socialist and political newcomer, defeated longtime Rep. Diana DeGette in Denver’s 1st Congressional District, according to a race call by the Associated Press. Kiros led by approximately 6 to 7 points (49% to 44%) with 78% of votes counted, as NPR reported.
Kiros, an Ethiopian American and former lawyer who was fired from her job after refusing to remove a social media post criticizing law firms’ stance on Israel and Palestine, is poised to become the first Black woman to represent Colorado in Congress and the first Gen Z woman elected to Congress. She centered her platform around “working families, establishing universal health care, child care and elder care” and committed to not accepting any corporate PAC money.
“Denver voters of all ages, of all races, of all religions sent a clear message: we will not wait,” Kiros said in her victory speech, as NPR reported. “Denver, the future is being written right now. Nothing is set in stone.”
DeGette, who has served in Congress for nearly 30 years and is a member of the Congressional Progressive Caucus, was forced to engage with Kiros’s challenge after initially attempting to ignore it. The incumbent defended her tenure on the campaign trail, emphasizing her progressive record on healthcare and climate policy.
Bennet’s Stunning Defeat
In the marquee race of the night, Colorado Attorney General Phil Weiser defeated U.S. Sen. Michael Bennet in the Democratic primary for governor, with the Associated Press calling the race at 7:55 p.m. when Weiser led by 10 percentage points. The result marks the first time a sitting U.S. senator has lost a gubernatorial primary since 2010, as The Colorado Sun reported.
Bennet, a 2020 presidential candidate who entered the governor’s race in April 2025 with a 31-point lead in internal polling, saw his advantage evaporate over the following year. He struggled throughout the campaign to answer a persistent question: why did he want to leave the Senate to become governor?
“Tonight’s results are not what we wanted,” Bennet said at his concession speech. “We came up short. And while that is disappointing — and I’d be lying if I said I wasn’t — I do not regret for a second the campaign that we ran or the cause that we fought for.”
Weiser, who jumped into the race months before Bennet, overcame significant disadvantages in name recognition and campaign spending. Bennet was backed by the super PAC Rocky Mountain Way, which raised $11 million including $5.1 million from former New York Mayor Michael Bloomberg. Weiser’s supporting super PAC raised only $1.4 million, though Weiser directly raised $6.8 million to Bennet’s $5 million.
“You all sent a very clear message: the future of Colorado will not be decided by out-of-state billionaires,” Weiser told supporters at his victory party, pledging to make government “work for all of us, not only the wealthy few.”
A Key House Battle Takes Shape
In Colorado’s 8th Congressional District — one of only 18 districts rated as a toss-up by the Cook Political Report — state Rep. Manny Rutinel won the Democratic nomination, defeating former state Rep. Shannon Bird. He will face incumbent Republican Rep. Gabe Evans in November in a district that is approximately 40% Latino, as NBC News noted.
Rutinel, who has a Dominican background, focused his campaign on immigration issues and accused Bird of not being tough enough in opposing ICE. The race is expected to be one of the most expensive and competitive House contests in the country, with significant implications for control of the chamber — Republicans currently hold 218 seats to Democrats’ 212.
The Anti-Incumbent Wave and Its Limits
The Colorado results are part of a broader national pattern. DSA-backed candidates won two primaries in New York the previous week, and the movement has also advanced candidates to November elections for mayor in Washington, D.C., and Los Angeles.
However, the anti-establishment wave has limits. State Sen. Julie Gonzales, a progressive challenger to incumbent Sen. John Hickenlooper, lost by approximately 7 points despite outperforming expectations. As The Colorado Sun analyzed, Gonzales faced structural disadvantages: she announced her campaign only seven months before the primary (compared to Kiros’s year), ran a statewide race requiring far more resources, and lacked the same level of organized left-wing support.
“Last night was sort of that primal scream,” said Eric Sondermann, a Colorado political commentator, referring to progressive voters expressing frustration with the Democratic establishment.
What’s Next
Weiser is heavily favored in November, given that Republicans haven’t won a statewide race in Colorado since 2016. The GOP gubernatorial primary remained too close to call between state Sen. Barbara Kirkmeyer, Victor Marx, and state Sen. Scott Bottoms.
Bennet has two years left on his Senate term, but his political future is uncertain after this loss. It remains unclear whether he will seek reelection in 2028.
Kiros, meanwhile, will face Republican Christy Peterson in the general election in a heavily Democratic district, making her all but certain to head to Washington. If successful, she would join Reps. Alexandria Ocasio-Cortez and Rashida Tlaib as one of only a handful of democratic socialists in Congress — potentially shifting the Democratic caucus further left on issues ranging from Gaza to healthcare to corporate money in politics.