Iowa's 4th Congressional District, a conservative northwest stronghold with an R+15 partisan lean, drives trader consensus toward a 89% implied probability for a Republican House winner in the November 2026 general election, reflecting historical blowout margins for GOP incumbents like Randy Feenstra, who is vacating the open seat for a gubernatorial bid. Recent Republican primary withdrawals—including state Rep. Matt Windschitl in early February and Ryan Rhodes about a month ago—have consolidated the June 2 GOP field around stronger fundraisers, easing the party's path despite a crowded primary. Democrats face steep barriers with a thin field of lesser-known challengers like Jermaine Decker, lacking competitive polling or resources in this battleground-poor district, keeping their odds at 9.5% amid latest FEC reports showing GOP fundraising dominance.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedIA-04 House Election Winner
IA-04 House Election Winner
Republican Party
89%
Democratic Party
10%
Republican Party
89%
Democratic Party
10%
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, 11:08 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...Iowa's 4th Congressional District, a conservative northwest stronghold with an R+15 partisan lean, drives trader consensus toward a 89% implied probability for a Republican House winner in the November 2026 general election, reflecting historical blowout margins for GOP incumbents like Randy Feenstra, who is vacating the open seat for a gubernatorial bid. Recent Republican primary withdrawals—including state Rep. Matt Windschitl in early February and Ryan Rhodes about a month ago—have consolidated the June 2 GOP field around stronger fundraisers, easing the party's path despite a crowded primary. Democrats face steep barriers with a thin field of lesser-known challengers like Jermaine Decker, lacking competitive polling or resources in this battleground-poor district, keeping their odds at 9.5% amid latest FEC reports showing GOP fundraising dominance.
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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