Democratic Socialists Win Key Primaries, Deepening Party Split as Shapiro Warns of 'Major Battle' Ahead

Progressive and democratic socialist candidates scored a string of primary victories in 2025, deepening a public rift with centrist Democrats.

A 29-year-old democratic socialist unseated Diana DeGette, a 15-term incumbent congresswoman, in a deep-blue Denver district — one of the most striking upsets in a night of progressive primary wins that stretched from New York to Colorado. Melat Kiros's defeat of DeGette, combined with other DSA-backed victories, marked a tangible shift in the Democratic Party's internal balance of power. In Michigan, Abdul El-Sayed — endorsed by both Bernie Sanders and Alexandria Ocasio-Cortez — led polls in a competitive Democratic Senate primary against Haley Stevens and Mallory McMorrow. AOC's endorsement drew particular attention as a signal of how national progressive figures are actively working to reshape the Senate's ideological composition. In New York, candidates who have publicly stated their belief that Israel has committed genocide won their primaries, including Darializa Avila Chevalier, raising questions among party strategists about whether the Democratic Party's center of gravity on Israel-Palestine policy is shifting. Newly elected New York City Mayor Zohran Mamdani, himself a democratic socialist, argued that he and the allies he endorsed carry a 'national message' that speaks to Americans 'coast to coast.' The wins triggered sharp intra-party reactions. Pennsylvania Governor Josh Shapiro publicly criticized Avila Chevalier on CNN's 'State of the Union,' saying he has 'profound differences' with her while acknowledging her district's right to elect her, and warned that a major battle for the future of the party is coming. Shapiro had been seen as a potential centrist counterweight, but he drew criticism from commentators after separately calling for 'radical reform' of the Supreme Court on MSNBC's 'Morning Joe,' joining Kamala Harris and Pete Buttigieg in embracing court-packing — a move that undercuts his centrist brand. Centrist Democrats more broadly, with some members of the party's old guard reportedly abandoning the 'blue no matter what' posture, called for party leaders to speak out and pushed for a more formal organizational break with the progressive wing. Republicans, meanwhile, seized on the results to publicly label the Democratic Party a 'socialist party,' framing the primaries as evidence of a broader ideological transformation. DSA membership has surged alongside increased pro-Palestinian activism, reshaping the terms of debate over not only who runs but how a campaigning movement translates into governing.

Why it matters

The results accelerate a structural divide inside the Democratic Party between its progressive and centrist factions at a moment when the party is already navigating questions of identity and electoral strategy. Candidates' positions on Israel and Gaza have emerged as a concrete litmus test that could influence primaries well beyond this cycle.

What's next

The Michigan Senate primary result, still pending at the time of reporting, will serve as a key indicator of how far progressive momentum can carry in a statewide race.

Key facts

• Melat Kiros, 29, defeated Diana DeGette, who had held her Colorado House seat for 15 terms, in a Denver Democratic primary
• AOC endorsed Abdul El-Sayed in the Michigan Democratic Senate primary, where he led polls against Haley Stevens and Mallory McMorrow
• El-Sayed also carries a Bernie Sanders endorsement
• New York candidates who stated a belief that Israel has committed genocide won their primaries
• Zohran Mamdani, a democratic socialist, is the newly elected New York City mayor and endorsed several of the winning progressive candidates
• Centrist Democrats are reportedly considering a formal organizational split from the progressive wing in response to the primary results

Bias & framing notes

All six sources are from The Guardian, which limits independent corroboration and introduces a consistent editorial perspective. The Guardian's framing leans toward presenting progressive wins as a meaningful political wave, while centrist Democratic concerns are framed primarily as 'backlash' rather than substantive policy disagreement. The headline describing moderates as 'old guard' reflects editorial framing rather than neutral description. No conservative or centrist outlets were included to provide a contrasting interpretation of the same events.

NewsClear — neutral news & congressional tracking · Bill of the Week