Progressive Veteran Retains Support in Primary Clash
Incumbent U.S. Senator Ed Markey secured the Democratic nomination for Senate in Massachusetts on Tuesday, September 1, 2026, defeating a primary challenge from U.S. Representative Seth Moulton, according to a race call projected by The Associated Press. The victory ensures the 80-year-old lawmaker will advance to the general election in November, turning back a high-profile campaign centered on generational change within the party leadership.
Markey, who has served in the U.S. Congress since before the 47-year-old Moulton was born, framed his primary success as a triumph for progressive priorities. Addressing supporters on election night, Markey described the outcome as a testament to the strength of the progressive movement, emphasizing the role of grassroots momentum and younger voters in propelling his campaign forward.
Generational Arguments and Institutional Endorsements
Throughout the campaign, Moulton focused heavily on Markey’s age, pointing out that the senator would be 86 years old at the conclusion of his next six-year term if reelected. Launching his bid the previous October, Moulton argued that national Democrats needed to learn lessons from recent high-profile tenure controversies involving figures like Ruth Bader Ginsburg, Dianne Feinstein, and Joe Biden. Moulton, along with media endorsements including The Boston Globe, suggested that prolonged tenure could compromise effective representation.
Despite these arguments, Markey maintained strong support among the state’s progressive base. The co-sponsor of the Green New Deal and supporter of Medicare for All relied on a coalition of prominent national and local figures, securing endorsements from U.S. Senators Elizabeth Warren and Bernie Sanders, as well as U.S. Representatives Alexandria Ocasio-Cortez and Ayanna Pressley. Youth-led organizations, including the Sunrise Movement and the College Democrats of Massachusetts, also backed the incumbent.
Markey pushed back against suggestions that age hindered his ability to serve, telling WBUR prior to the vote that his policy initiatives remained forward-looking and that he would step down if he ever found himself unable to execute his duties effectively. Following the race call, Moulton issued a concession statement confirming he had called Markey to offer his endorsement and assistance ahead of the general election to keep the seat in Democratic hands.
Down-Ballot Impact and November Outlook
Moulton’s decision to enter the Senate race left his seat in Massachusetts’s 6th Congressional District open. In the concurrent Democratic primary for that northeastern district, former presidential advisor Dan Koh secured the nomination, according to AP projections reported by WGBH. Koh emerged from a five-candidate field with 42.3% of the vote with nearly two-thirds counted, beating state Representative Tram T. Nguyen.
In the upcoming November election, Markey will face Republican nominee John Deaton, a lawyer who previously ran an unsuccessful challenge against Senator Elizabeth Warren two years prior. Koh will contest the 6th District seat against Republican challenger Micah Quinney Jones.
This outcome marks the second time Markey has successfully defeated a younger, primary opponent running on a generational argument, following his 2020 victory against then-U.S. Representative Joe Kennedy III. In a state that has not elected a Republican to the U.S. Congress since Scott Brown’s special election victory in 2010, Markey enters the general election campaign as the heavy favorite.