Incumbent Republican Rep. Mike Bost's unopposed March primary victory solidified trader consensus at 93.5% for a GOP hold in Illinois' 12th Congressional District, a solidly Republican seat per Cook Political Report ratings spanning southern Illinois. Democratic nominee Julie Fortier, a metro-east resident who also ran unopposed, launched her challenge in late 2025 emphasizing healthcare and jobs but lacks the name recognition or fundraising to threaten Bost's established incumbency advantage, honed after surviving a bruising 2024 primary. Absent major developments like scandals, health issues, or a national Democratic wave driving turnout in suburban pockets, the November 3 general election path favors Republicans, with forecasting models implying 25+ point leads aligning with market pricing.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedIL-12 House Election Winner
IL-12 House Election Winner
$17,926 Vol.
$17,926 Vol.
Republican Party
94%
Democratic Party
5%
$17,926 Vol.
$17,926 Vol.
Republican Party
94%
Democratic 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...Incumbent Republican Rep. Mike Bost's unopposed March primary victory solidified trader consensus at 93.5% for a GOP hold in Illinois' 12th Congressional District, a solidly Republican seat per Cook Political Report ratings spanning southern Illinois. Democratic nominee Julie Fortier, a metro-east resident who also ran unopposed, launched her challenge in late 2025 emphasizing healthcare and jobs but lacks the name recognition or fundraising to threaten Bost's established incumbency advantage, honed after surviving a bruising 2024 primary. Absent major developments like scandals, health issues, or a national Democratic wave driving turnout in suburban pockets, the November 3 general election path favors Republicans, with forecasting models implying 25+ point leads aligning with market pricing.
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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