Incumbent Republican Mike Bost's commanding position in the solidly Republican IL-12 district, rated R+22 on the Cook Partisan Voting Index, underpins trader consensus implying a 93.5% probability of a GOP House election win on November 3, 2026. Bost advanced unopposed in the March 17 Republican primary with over 81,000 votes, signaling party unity after surviving a competitive 2024 primary, while Democrat Julie Fortier also ran unopposed but drew far fewer primary votes amid meager fundraising ($41,000 raised vs. Bost's $1.1 million as of late March). Bost's recent landslide general election margins exceeding 74% reflect the district's rural southern Illinois conservative base. No major developments have emerged since primaries, but scenarios like a personal scandal, health event, or extraordinary Democratic midterm turnout surge could narrow odds, though structural barriers remain high.
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
$18,406 Vol.
$18,406 Vol.
Republican Party
94%
Democratic Party
7%
$18,406 Vol.
$18,406 Vol.
Republican Party
94%
Democratic 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...Incumbent Republican Mike Bost's commanding position in the solidly Republican IL-12 district, rated R+22 on the Cook Partisan Voting Index, underpins trader consensus implying a 93.5% probability of a GOP House election win on November 3, 2026. Bost advanced unopposed in the March 17 Republican primary with over 81,000 votes, signaling party unity after surviving a competitive 2024 primary, while Democrat Julie Fortier also ran unopposed but drew far fewer primary votes amid meager fundraising ($41,000 raised vs. Bost's $1.1 million as of late March). Bost's recent landslide general election margins exceeding 74% reflect the district's rural southern Illinois conservative base. No major developments have emerged since primaries, but scenarios like a personal scandal, health event, or extraordinary Democratic midterm turnout surge could narrow odds, though structural barriers remain high.
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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