The Illinois 9th congressional district's consistent Democratic performance in recent cycles, combined with Daniel K. Biss securing the nomination after winning the March 2026 primary, drives the 94.5% implied probability for the Democratic nominee. Race ratings from Cook Political Report, Sabato's Crystal Ball, and others classify the seat as solid or safe Democratic, reflecting its voter composition and history of large margins for the party. John Elleson, the Republican nominee, faces structural headwinds in a district where national conditions and local fundamentals have long favored Democrats. Scenarios that could narrow the gap include a substantial national Republican wave, a significant late scandal or health issue involving Biss, or turnout anomalies exceeding historical patterns, though current evidence shows limited signs of such shifts before 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. · UpdatedIL-09 House Election Winner
$31,610 Vol.
$31,610 Vol.
Democratic Party
95%
Republican Party
5%
$31,610 Vol.
$31,610 Vol.
Democratic Party
95%
Republican Party
5%
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 Illinois 9th congressional district's consistent Democratic performance in recent cycles, combined with Daniel K. Biss securing the nomination after winning the March 2026 primary, drives the 94.5% implied probability for the Democratic nominee. Race ratings from Cook Political Report, Sabato's Crystal Ball, and others classify the seat as solid or safe Democratic, reflecting its voter composition and history of large margins for the party. John Elleson, the Republican nominee, faces structural headwinds in a district where national conditions and local fundamentals have long favored Democrats. Scenarios that could narrow the gap include a substantial national Republican wave, a significant late scandal or health issue involving Biss, or turnout anomalies exceeding historical patterns, though current evidence shows limited signs of such shifts before 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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