DENVER — Democratic socialist Melat Kiros defeated 15-term U.S. Representative Diana DeGette in Colorado's Democratic primary for a Denver-area congressional district on Tuesday, according to U.S. media projections, delivering one of the most significant incumbent defeats of the 2026 primary season.
Multiple U.S. media organizations called the race with about 78% of ballots counted, showing Kiros ahead by nearly 7,000 votes over DeGette, who has represented Colorado's 1st Congressional District since 1997.
Kiros, 29, is a former attorney and democratic socialist whose campaign emphasized Medicare for All, housing affordability, campaign finance reform and criticism of corporate influence in politics. She also drew national attention for her outspoken opposition to U.S. support for Israel's military campaign in Gaza, which she has described as genocide, a characterization rejected by Israel.
Her victory marked the latest success for left-wing insurgent candidates challenging established Democrats in safe Democratic districts. Political observers said the result followed a series of recent primary wins by candidates aligned with the Democratic Party's progressive wing.
DeGette, 68, is one of Colorado's longest-serving members of Congress and has been regarded as a leading House Democrat on healthcare issues. Despite her progressive voting record, including support for expanded healthcare access and abortion rights, she faced criticism from some activists who argued the party needed new leadership and a more confrontational approach to Democratic leadership and foreign policy.
Kiros' campaign also generated controversy. She was dismissed from a law firm after refusing to remove a public post criticizing law firms' responses to the Israel-Palestinian conflict, and critics objected to her alliance with socialist political commentator Hasan Piker. Supporters argued those episodes reflected her willingness to challenge established institutions.
The Denver-based district is heavily Democratic, making Kiros the strong favorite to win the November general election against the Republican nominee.
The Colorado primary results added to a broader pattern of competitive Democratic contests nationwide as voters weighed generational change, ideological direction and the party's strategy ahead of the 2026 midterm elections.
