The Massachusetts 9th congressional district’s strong Democratic lean, reflected in its D+6 Cook Partisan Voter Index and consistent Solid Democratic or Safe Democratic ratings from nonpartisan forecasters, underpins trader consensus favoring the Democratic nominee at 93.5 percent. Longtime incumbent Bill Keating, first elected in 2010, faces only a Democratic primary challenge from community organizer Craig Swallow ahead of the September 2026 primary, with no prominent Republican candidate yet positioned to contest the November general election. The district’s South Shore, Cape Cod, and South Coast geography has trended Democratic in recent cycles, limiting realistic paths for Republican gains absent major shifts in national conditions or candidate dynamics before filing closes in August.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedMA-09 House Election Winner
$10,411 Vol.
$10,411 Vol.
Democratic Party
93%
Republican Party
7%
$10,411 Vol.
$10,411 Vol.
Democratic Party
93%
Republican Party
7%
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 House elections are conclusively called by this market's resolution sources. A candidate without a ballot-listed affiliation to either the Democrat or Republican parties will be considered a member of one of these parties based on the party with which they most recently expressed their intent to caucus at the time all of the House elections are conclusively called by this market's resolution sources.
This market will resolve based on the result of the election as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the United States government, specifically the Federal Election Commission (https://www.fec.gov/).
Market Opened: Jan 28, 2026, 11:09 AM ET
Resolver
0x2F5e3684c...A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 House elections are conclusively called by this market's resolution sources. A candidate without a ballot-listed affiliation to either the Democrat or Republican parties will be considered a member of one of these parties based on the party with which they most recently expressed their intent to caucus at the time all of the House elections are conclusively called by this market's resolution sources.
This market will resolve based on the result of the election as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the United States government, specifically the Federal Election Commission (https://www.fec.gov/).
Resolver
0x2F5e3684c...The Massachusetts 9th congressional district’s strong Democratic lean, reflected in its D+6 Cook Partisan Voter Index and consistent Solid Democratic or Safe Democratic ratings from nonpartisan forecasters, underpins trader consensus favoring the Democratic nominee at 93.5 percent. Longtime incumbent Bill Keating, first elected in 2010, faces only a Democratic primary challenge from community organizer Craig Swallow ahead of the September 2026 primary, with no prominent Republican candidate yet positioned to contest the November general election. The district’s South Shore, Cape Cod, and South Coast geography has trended Democratic in recent cycles, limiting realistic paths for Republican gains absent major shifts in national conditions or candidate dynamics before filing closes in August.
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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