Incumbent Democrat Marcy Kaptur seeks reelection against Republican Derek Merrin in Ohio's 9th congressional district, a race shaped by 2025 redistricting that shifted boundaries to favor Republicans by roughly 10 points based on 2024 presidential results. Kaptur won the Democratic primary unopposed while Merrin secured the GOP nomination in May with 44% in a crowded field. Prediction markets reflect trader consensus favoring Democrats at 64.5% implied probability, driven by Kaptur's decades-long incumbency, local name recognition, and fundraising lead exceeding $4 million versus Merrin's $1.5 million. Forecasters rate the contest a toss-up or lean Democratic despite the district's Republican tilt, with the November 3 general election still featuring significant uncertainty from voter turnout and late-cycle dynamics.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedOH-09 House Election Winner
$29,651 Vol.
$29,651 Vol.
Democratic Party
65%
Republican Party
35%
$29,651 Vol.
$29,651 Vol.
Democratic Party
65%
Republican Party
35%
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: Dec 16, 2025, 12:48 PM 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 Democrat Marcy Kaptur seeks reelection against Republican Derek Merrin in Ohio's 9th congressional district, a race shaped by 2025 redistricting that shifted boundaries to favor Republicans by roughly 10 points based on 2024 presidential results. Kaptur won the Democratic primary unopposed while Merrin secured the GOP nomination in May with 44% in a crowded field. Prediction markets reflect trader consensus favoring Democrats at 64.5% implied probability, driven by Kaptur's decades-long incumbency, local name recognition, and fundraising lead exceeding $4 million versus Merrin's $1.5 million. Forecasters rate the contest a toss-up or lean Democratic despite the district's Republican tilt, with the November 3 general election still featuring significant uncertainty from voter turnout and late-cycle dynamics.
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