Markey Defeats Moulton in MA Senate Primary, Retaining Progressive Edge

Key points

• Sen. Ed Markey defeated Rep. Seth Moulton in the Massachusetts Democratic Senate primary, winning by nearly 50 percentage points according to NBC News projections.
• Markey, 80, leveraged endorsements from Sen. Bernie Sanders, Sen. Elizabeth Warren, and Rep. Alexandria Ocasio-Cortez to frame himself as the more progressive candidate.
• Moulton, 47, spent $7.1 million on ads compared to Markey’s $3.9 million, according to AdImpact, but failed to convince voters of his generational change message.
• In the 8th Congressional District, moderate Rep. Stephen Lynch defeated progressive challenger Patrick Roath, despite Roath having a fundraising advantage.
• Dan Koh, a Biden White House alum, won the 6th Congressional District primary, benefiting from endorsements from former President Biden and former Vice President Kamala Harris.

Background

The 2026 Massachusetts primary was viewed as a critical test of the Democratic Party’s internal divisions between progressive and moderate wings. Prior coverage highlighted Markey’s strong polling lead and the contrast between his long tenure and Moulton’s call for generational renewal. The race was also part of a broader national trend where younger challengers had successfully ousted veteran Democrats in other states, making Markey’s victory notable for defying this pattern.

How outlets are covering it

NBC News and CNN both emphasized Markey’s victory as a triumph for the progressive wing, highlighting his endorsements from Sanders and Warren. CNN noted that while Moulton had a spending advantage, he failed to convince voters of his generational message. Politico highlighted the unusual nature of the race, where the aging incumbent was the more progressive candidate, contrasting with other generational fights where younger challengers were more left-leaning. NBC Boston focused on the broader primary results, noting that while Markey won, other incumbents like Stephen Lynch also secured their nominations, indicating a mixed outcome for the party’s progressive base.

Why it matters

Markey’s victory ensures that a progressive voice remains in the Senate, potentially influencing national policy debates on healthcare and climate. The result also signals that, despite generational challenges, veteran incumbents can retain support if they align with the party’s progressive base. The mixed results in other Massachusetts races suggest that the party’s internal divisions remain significant, with moderates and progressives both finding success in different districts.

What to watch

Markey will face Republican John Deaton in the general election, where he is favored to win. The outcome of the 6th and 8th District primaries will shape the composition of the Massachusetts delegation in Congress. The results may also influence the broader Democratic strategy for the 2026 midterms, particularly regarding the balance between progressive and moderate candidates.