Anti-establishment progressives saw off some seasoned office-holders in Democratic primary contests in the US state of Colorado on Tuesday, as the party ⁠struggles with an internal battle over how far to the left it can shift without ruining its prospects for taking control of US Congress in November mid-term elections.

The big surprise of the night was the defeat in Colorado’s first district of incumbent member of the House of Representatives Progressive Caucus Dianna DeGette by a 29-year-old labour rights activist and lawyer, Melat Kiros.

More broadly, the primary ballots are widely seen as an indicator of which key issues are motivating US voters.

Here are some key takeaways from Colorado’s Tuesday ballots:

Anti-establishment candidates make gains

Similar to what happened in New York’s primaries, voters delivered a blow to moderate Democrats, while leftist candidates made gains.

Kiros, who moved to the US from Ethiopia as a ⁠baby, beat DeGette in the Denver area despite being outgunned more than 2-1 in terms of funding and having called for a full arms embargo on Israel for even defensive weapons. DeGette is in favour of sending defensive weapons.

Kiros was fired from her job after refusing to delete a social media post that criticised law firms for their stance on Israel and Palestine and has called Israel’s actions in Gaza a genocide.

Her win is being seen as a stunning victory for a first-time candidate against a nearly 30-year incumbent, and a major win for the Democratic Socialists of America. Kiros, who won more than double the votes DeGette did, is expected to win against the Republicans in November and reach Congress in January.

A smaller divide separated the two Democrats competing for the House of Representatives seat in the 8th District. The candidate considered more progressive, State Representative Manny Rutinel, won over former state Representative Shannon Bird.

However, Democratic Senator John Hickenlooper saw off a primary challenge by self-described “insurgent progressive” state Senator Julie Gonzales.

Progressives could flip a district

Colorado’s 8th Congressional District is relatively new, stretching from the northern suburbs of Denver up through farming country, and has flipped party control in recent elections.

Rutinel, a progressive, is now in a position to vie for a Republican-held US House of Representatives seat in the midterm election on November 3. This is a race that could help determine whether Democrats win control of the 435-seat chamber that is narrowly held by Republicans.

Rutinel will face Republican US Representative ⁠Gabe Evans in what is expected to be a competitive contest. Party leaders thought the more moderate Bird was best equipped to challenge Evans, but Rutinel, who had the more progressive record, beat Bird on Tuesday.

Democrats expected to hold governorship

Phil Weiser, a state attorney general, won the Democratic primary and will be the favourite to win the contest for governor of the state in November. Term-limited Democratic Governor Jared Polis will depart after two terms governing with a more moderate touch, at times stymying progressive state lawmakers.

However, US Senator Michael Bennet was defeated in the gubernatorial primary despite holding a seat in the Senate for more than 17 years, where he has gained a reputation as a pragmatist. He ‌previously served as the superintendent of Denver’s public schools.

⁠The race for the Democratic nomination for governor was largely viewed as a contest over which candidate is best positioned to defend Colorado against President Donald Trump, who has frozen federal funds to the state and vetoed a major drinking water project in Colorado, where voters have trended Democratic in elections over the past 20 years.

The somewhat less-establishment Weiser was able to far outpace Bennet in terms of funding, outspending him by $1m.

Weiser, who formerly served in the presidential administrations of Barack Obama and Bill Clinton, is considered to be more sympathetic to the party’s leftward flank.

Trump remains centre stage

After his victory, Senator Hickenlooper quickly turned his attention to Trump.

“Coloradoans have once again made their voices clear. We are not going to accept Trump’s broken promises and cost of living emergency, or his constant corruption,” he said in a video posted to YouTube.

Kiros took the stage under a sign that read “Power to the People”, and said she was part of “a movement”. “We are just getting started,” she told supporters.

She added that she planned to take the fight to “Donald Trump and the oligarchy”, abolish US Immigration and Customs Enforcement (ICE), pass “Medicare for all” and end the “genocide in Palestine”.

The incumbent, DeGette, had argued that experience in Congress is needed right now to combat Trump, while Kiros accused her of ineffectiveness.