Incumbent Democrat Mike Thompson's entrenched hold on California's 4th Congressional District, rated Solid Democratic with a D+17 Cook Partisan Voter Index, underpins trader consensus pricing a Democratic general election win at 91.5% following his dominant 66%+ victories in 2024 and 2022. Recent FEC filings through March 31 confirm Thompson's $2.6 million cash on hand dwarfs challenger Eric Jones's $1.5 million and negligible Republican totals amid a fragmented six-candidate GOP primary field ahead of the June 2 top-two primary. Redistricting preserved the Democratic lean despite boundary tweaks. While a consolidated Republican primary surge or scandal could challenge this, historical base rates favor the incumbent in safe seats.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedCA-04 House Election Winner
CA-04 House Election Winner
Democratic Party
92%
Republican Party
9%
Democratic Party
92%
Republican Party
9%
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 27, 2026, 11:54 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 Mike Thompson's entrenched hold on California's 4th Congressional District, rated Solid Democratic with a D+17 Cook Partisan Voter Index, underpins trader consensus pricing a Democratic general election win at 91.5% following his dominant 66%+ victories in 2024 and 2022. Recent FEC filings through March 31 confirm Thompson's $2.6 million cash on hand dwarfs challenger Eric Jones's $1.5 million and negligible Republican totals amid a fragmented six-candidate GOP primary field ahead of the June 2 top-two primary. Redistricting preserved the Democratic lean despite boundary tweaks. While a consolidated Republican primary surge or scandal could challenge this, historical base rates favor the incumbent in safe seats.
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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