Trader consensus gives Democrats a 93.5% implied probability to win Massachusetts's 4th Congressional District House seat, driven by its D+11 Cook Partisan Voting Index, longstanding Democratic dominance, and incumbent Rep. Jake Auchincloss's fundraising supremacy with over $7 million raised—far outpacing primary challengers like Ihssane Leckey and recent entrant Chris Boyd. Republican physicist Tom Stalcup's April campaign launch emphasizing healthcare reform has failed to move markets in the deep-blue district, where Auchincloss cruised to victory in prior cycles. The September 1 Democratic primary poses the main near-term test, though upset odds remain low absent scandals, health issues, or a broader Republican midterm wave flipping incumbency advantages.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedMA-04 House Election Winner
MA-04 House Election Winner
$34,331 Vol.
$34,331 Vol.
Democratic Party
94%
Republican Party
4%
$34,331 Vol.
$34,331 Vol.
Democratic Party
94%
Republican Party
4%
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...Trader consensus gives Democrats a 93.5% implied probability to win Massachusetts's 4th Congressional District House seat, driven by its D+11 Cook Partisan Voting Index, longstanding Democratic dominance, and incumbent Rep. Jake Auchincloss's fundraising supremacy with over $7 million raised—far outpacing primary challengers like Ihssane Leckey and recent entrant Chris Boyd. Republican physicist Tom Stalcup's April campaign launch emphasizing healthcare reform has failed to move markets in the deep-blue district, where Auchincloss cruised to victory in prior cycles. The September 1 Democratic primary poses the main near-term test, though upset odds remain low absent scandals, health issues, or a broader Republican midterm wave flipping incumbency advantages.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
Beware of external links.
Beware of external links.
Frequently Asked Questions