Markey Defeats Moulton About 66 to 34 in Massachusetts Senate Primary

A called race and a published share

On Tuesday night, September 1, 2026, the Associated Press projected that Sen. Ed Markey had defeated Rep. Seth Moulton in the Massachusetts Democratic primary for U.S. Senate (Associated Press via NBC News, September 1, 2026; POLITICO, September 1, 2026). Ballotpedia's tabulated results, sourced to The New York Times interactive, put Markey at 65.6 percent and Moulton at 34.4 percent on a count of 208,325 votes (Ballotpedia, September 1, 2026). Roll Call reported Markey leading about 65 percent to 35 percent with 81 percent of the expected vote counted (Roll Call, September 2, 2026).

Markey is 80. Moulton is 47. The age gap was the campaign's loudest frame. The published preference stack was not close. Print the margin. Do not invent a cliffhanger the returns did not show.

Money did not buy the nomination

NBC News, citing AdImpact, reported that Moulton and his allies spent about $7.1 million on ads while Markey and his allies spent about $3.9 million (NBC News, September 1, 2026). Federal Election Commission cycle totals compiled by Boston.com showed Moulton raising about $6.2 million and Markey about $5.3 million through mid August, with Moulton also ahead in cash on hand (Boston.com, updated September 1, 2026). The challenger had more television and more receipts. The incumbent still cleared about two thirds of the Democratic primary vote.

Markey campaigned on progressive credentials that include coauthorship of the Green New Deal and support for Medicare for All, with public endorsements from Sens. Bernie Sanders and Elizabeth Warren and Rep. Alexandria Ocasio-Cortez (POLITICO, September 1, 2026; The New York Times, September 1, 2026). Moulton argued for generational change and carried endorsements from New Jersey Gov. Mikie Sherrill and groups such as VoteVets (POLITICO, September 1, 2026). Ideology and organization beat the age argument inside a deep blue primary electorate. That is a Massachusetts fact, not a national mandate.

House races on the same ballot

Incumbent House Democrats also held. Rep. Richard Neal defeated Jeromie Whalen 55.2 percent to 44.8 percent in the 1st District. Rep. Stephen Lynch defeated Patrick Roath 56.9 percent to 43.1 percent in the 8th District (Ballotpedia, September 1, 2026). In the open 6th District seat that Moulton left to run statewide, former Biden administration aide Dan Koh led with 42.2 percent, ahead of state Rep. Tram Nguyen at 29.5 percent (Ballotpedia, September 1, 2026; New York Post, September 1, 2026).

On the Republican side, lawyer John Deaton was unopposed for the Senate nomination and will face Markey on November 3. Deaton lost to Sen. Elizabeth Warren in 2024 (The New York Times, September 1, 2026; Roll Call, September 2, 2026). Cook Political Report rates Massachusetts Solid Democrat among seats up this cycle. US Political Rank tracks that board on its ranking of 2026 Senate races.

What Tuesday settles for the Senate map

Massachusetts was never a path to a four seat Democratic net gain. Cook's Senate summary among seats up still reads Solid Democrat 9, Likely Democrat 1, Lean Democrat 3, Toss Up 6, Likely Republican 2, Solid Republican 14 on the August 20 board that still governs public talk of the map (Cook Political Report Senate ratings, August 20, 2026). Republicans hold a 53 to 47 majority. Democrats need a net plus four for majority control in 2027 because Vice President JD Vance would break a 50 to 50 tie.

What Tuesday settles is the Democratic nominee in a Solid Democrat state and a clearer general election matchup. What it does not settle is Michigan, Maine, Ohio, Alaska, Iowa, or Texas. Jessica Taylor at Cook published a September 1 overview arguing the competitive Senate battlefield remains about nine seats, with Kansas and Nebraska still only Likely Republican and deeper red states still Solid Republican (Cook Political Report, September 1, 2026).

Final preprimary surveys had already pointed the same direction. Emerson College polling of Massachusetts Democratic primary voters August 28 to 29 put Markey near 60 percent and Moulton near 33 percent. A University of Massachusetts survey in the same window landed near 60 to 32 (prior US Political Rank primary eve coverage citing Emerson and UMass, August 30 to September 1, 2026). The certified preference stack matched the late instruments more closely than the ad ledger. That is useful for readers who treat money as destiny. It is also useful for readers who treat polls as destiny. Both tools missed if they predicted a nail biter. Neither tool replaces a canvass.

A finished Massachusetts primary is a finished Massachusetts primary. Election Day is 62 days from September 2. The next primary date that matters for an open Democratic Senate seat is New Hampshire on September 8, where Sen. Jeanne Shaheen's retirement leaves a real November fight after the nominees are named (The New York Times 2026 primary calendar, updated September 1, 2026). Print Tuesday's receipts. Then move the clipboard to the next gym.