The 28-year-old, first-time candidate challenging Democratic U.S. Rep. Diana DeGette in this year’s primary soundly defeated the 15-term incumbent in a delegate preference poll conducted Saturday at a county party assembly in Denver.

Melat Kiros, the daughter of Ethiopian immigrants and a former corporate attorney, received nearly twice as many votes as DeGette in a poll to allocate delegates to the 1st Congressional District assembly, which is scheduled to nominate candidates to Colorado’s primary ballot on March 27.

While both are on target to qualify for the June 30 primary in the Denver-based district, the drubbing marks a wake-up call for the 68-year-old DeGette, who has represented the state’s most reliably Democratic seat in Congress since 1997.

Kiros, who launched her campaign in July, got 63% of the vote to DeGette’s 35%, with 2% uncommitted, according to preliminary, unofficial results.

“This victory belongs to every person in Denver who has been showing up to community meetings, talking to their neighbors, and demanding better from their representation,” Kiros said in a statement after the vote.

“Denver has changed,” Kiros added. “Rents have doubled. Healthcare costs are crushing families. And for 30 years, our congresswoman has cashed checks from corporate PACs while the people she represents fall further behind. Today, Denver Democrats said: enough.”

A spokeswoman for DeGette’s campaign told Colorado Politics that the congresswoman looks forward to the primary.

“Diana DeGette has worked hard for Denver for over 30 years and is grateful she is on track to make the ballot through the assembly process, despite the major technical issues with the party’s software platform and serious questions about the process,” Jennie Peek-Dunstone said in a text message. “She enjoyed connecting with Democrats about the issues that matter to them.”

Peek-Dunstone noted that Democrats at numerous county assemblies encountered difficulty using the state party’s reporting platform, leading to some delegates departing before having a chance to vote and questions about whether everyone who cast paper ballots were eligible.

Democrats at the Denver county assembly, held at Denver South High School, used the results to apportion delegates elected to the congressional district assembly, the next step in the nominating process, where candidates who clear 30% delegate support will advance to the primary.

The 1st CD covers Denver and a few precincts in neighboring Arapahoe County, which is sending a handful of delegates to the district assembly.

A third Democrat, University of Colorado Regent Wanda James, is pursuing a berth in the 1st CD primary via petition. She faces a Wednesday deadline to turn in the required 1,500 valid signatures belonging to Democrats who live in the district.

After wining renomination for years without breaking a sweat, DeGette has survived multiple primary challenges in the last decade by wide margins and won reelection by even wider margins. In the last election, she defeated Republican nominee Valdamar Archuleta by 55 points.

Republicans have yet to field a candidate in the district.

Primary ballots are set to go out in early June. They’re due back to county clerks by June 30.

Editor’s note: This is a developing story and will be updated.