Incumbent Democrat Ed Markey maintains a lead in the 2026 Massachusetts Senate Democratic primary despite a tightening race against Representative Seth Moulton, per an Emerson College poll released four days ago showing Markey at 37% to Moulton's 32%, reinforcing trader consensus at 94.5% odds for a Democratic general election winner amid the state's D+15 partisan lean and historical dominance—no Republican has won this seat since 1976. Recent University of New Hampshire polling from late April further underscores wide general election margins, with Markey or Moulton topping potential GOP challenger John Deaton by 24–31 points. Primaries on September 1 could test Markey's resilience at age 80, but scenarios like a high-profile Republican recruit, Markey health issues, or a national GOP wave would be needed to challenge this positioning ahead of the November general election.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedMassachusetts Senate Election Winner
Massachusetts Senate Election Winner
$12,986 Vol.
$12,986 Vol.

Democrat
95%

Republican
4%
$12,986 Vol.
$12,986 Vol.

Democrat
95%

Republican
4%
A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.
Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Market Opened: Oct 13, 2025, 5:07 PM ET
Resolver
0x2F5e3684c...A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.
Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Resolver
0x2F5e3684c...Incumbent Democrat Ed Markey maintains a lead in the 2026 Massachusetts Senate Democratic primary despite a tightening race against Representative Seth Moulton, per an Emerson College poll released four days ago showing Markey at 37% to Moulton's 32%, reinforcing trader consensus at 94.5% odds for a Democratic general election winner amid the state's D+15 partisan lean and historical dominance—no Republican has won this seat since 1976. Recent University of New Hampshire polling from late April further underscores wide general election margins, with Markey or Moulton topping potential GOP challenger John Deaton by 24–31 points. Primaries on September 1 could test Markey's resilience at age 80, but scenarios like a high-profile Republican recruit, Markey health issues, or a national GOP wave would be needed to challenge this positioning ahead of the November general election.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated



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