(NEW YORK) -- Melat Kiros, a 29-year-old attorney and democratic socialist, will win the Democratic primary for U.S. House in Colorado's 1st Congressional District, the Associated Press projected, triumphing over longtime incumbent Rep. Diana DeGette and notching another win for the left wing of the Democratic Party over established incumbents.
Kiros' projected win is a stunning victory for a political newcomer and yet another apparent sign of Democratic voter discontent with incumbents, just a week after three insurgent candidates triumphed against incumbent or incumbent-backed candidates in New York City congressional races.
The primary challenger, who was fired from her law firm in 2023 after writing an open letter criticizing her employers' response to pro-Palestinian protests, campaigned on channeling voters' anger with the political system; her campaign also tapped into the strength of local and national branches of the Democratic Socialists of America.
DeGette, who has served in the House for around three decades, had argued that her experience, including in leadership roles during President Donald Trump's impeachment proceedings, made her effective at pushing back against the Trump administration.
Kiros will face Republican nominee Christie Peterson, an accountant, who was uncontested in the GOP primary. The Cook Political Report rates the seat, which is based around Denver, as solidly Democratic.
Another victory for progressive wing in gubernatorial primary
The Associated Press also projected on Tuesday night that Attorney General Phil Weiser will win the Democratic primary for governor in Colorado, triumphing against Sen. Michael Bennet.
The results could potentially be seen as another sign of Democratic voters' dissatisfaction with Washington and incumbents in Congress, even though the race was technically for a state position.
Weiser, who served in the Obama administration and as Colorado's attorney general since 2019, had positioned himself as the insurgent in the race against Bennet, linking the longtime senator to Washington and gridlock in Congress. Incumbent Democratic Gov. Jared Polis is term-limited.
But there was better news for another congressman from Colorado. The Associated Press projected Tuesday night that incumbent Sen. John Hickenlooper will win the Democratic primary for Senate in Colorado, putting him on a glide path back to Congress as he runs for a second term.
Hickenlooper triumphed over a primary challenge from state Sen. Julie Gonzales, who ran a progressive campaign and notched the endorsement of left-leaning organizations.
Inside the Melat-DeGette race
Still, most of the attention was focused on the 1st Congressional District.
Ahead of Tuesday's primary, Kiros told ABC News she hoped to build on the movement's momentum from last Tuesday in New York.
"Ultimately, folks are really tired of the party failing to meaningfully represent the values and policies that are extremely popular with our base," she said. "And we're looking for leaders that are unbought and unafraid to stand up to a lot of these corporations and special interests that have gotten us into this mess in the first place."
Kiros has also been outspoken about criticism of Israel and its conduct in Gaza, another issue that has divided Democrats and played a major role in the New York primaries. She recently faced some pushback for not calling the June 2025 firebombing in Boulder, Colorado, of on a group of demonstrators calling for the release of Israeli hostages antisemitic, although she condemned the violence and said she is committed to combatting antisemitism.
Kiros told ABC News on Monday that the attack was “a horrific attack on a group of Jewish people that were just engaging in peaceful protest,” and said that she is committed to combatting hate in all forms, including antisemitism; that responsibility also includes “making sure that we are rejecting this conflation of the state of Israel's actions with Judaism and with the Jewish people, and making sure that we are preventing that kind of conflation from leading to the kind of horrific attacks that a lot of Jewish people are afraid of.”
While Kiros netted the endorsement of progressive stalwart Sen. Bernie Sanders, an independent, and some left-leaning groups, the race did not break down evenly along ideological fault lines.
DeGette is a leading member of the Congressional Progressive Caucus who has led Democratic messaging on abortion rights and served as a House impeachment manager during Trump's second impeachment trial.
Unlike some incumbent Democrats facing primaries, she has criticized Israel's handling of the war in Gaza and voted against additional U.S. military aid to Israel.
"Denver knows I don't back down. That's why I'm taking on Donald Trump to protect our reproductive freedom, abolish ICE, and pass Medicare for All. Together we'll win and deliver on our progressive values," DeGette said in a statement to ABC News before the primary.
In a recent interview with ABC affiliate KMGH-TV, DeGette argued that her time in Congress was an asset to her constituents.
But that long record also made her a target for frustrated progressives, who sense momentum after democratic socialists Darializa Avila Chevalier and Claire Valdez defeated establishment-backed Democrats in two New York City primaries -- including the chairman of the Congressional Hispanic Caucus -- last week, with the help of democratic socialist Mayor Zohran Mamdani.
"They see Melat as someone who has put up a fight -- not just against Republican fascism, but also against the Democratic establishment that has failed voters," Usamah Andrabi, communications director for Justice Democrats, told ABC News.
The group helped Kiros and her allies knock on tens of thousands of doors and make more than 200,000 calls to potential voters since last week, according to the Justice Democrats.
DeGette's record "is very progressive, and she's not a moderate," Doug Friednash, an attorney who was chief of staff to Hickenlooper, told ABC News. "A lot of young voters are demanding change ... they look at rising health care costs, gas prices, and there's a view that the establishment hasn't done enough."
Elsewhere, in Colorado's 8th District, a battleground seat currently held by a Republican, Democrat Manny Rutinel, a 31-year-old state representative, was projected by the Associated Press to win the primary for the Democratic nomination against former state lawmaker Shannon Bird.