Trader consensus heavily favors the Democratic Party at 88.5% implied probability to win California's 21st Congressional District House seat, driven by incumbent Jim Costa's strong reelection bid and proven track record in the Central Valley district. Recent mid-decade redistricting, finalized in early March 2026, has preserved Costa's favorable terrain despite forcing candidate scrambles statewide, with no major Republican challenger emerging to threaten his hold. While GOP candidates like Fresno businessman Kyle Kirkland and Lorenzo Rios announced candidacies late last year, they show limited fundraising or polling momentum ahead of the June 2 top-two primary. Incumbency advantage, district fundamentals, and Costa's moderate appeal among agricultural voters underpin the lopsided odds, though a national Republican wave or primary upset could narrow the gap.
Experimental AI-generated summary referencing Polymarket data · UpdatedCA-21 House Election Winner
CA-21 House Election Winner
NEW
NEW
Nov 3, 2026
Democratic Party
89%
Republican Party
11%
NEW
NEW
Nov 3, 2026
Democratic Party
$0 Vol.
89%
Republican Party
$0 Vol.
11%
This market will resolve according to the party of the candidate who wins the CA-21 congressional district seat in the U.S. House of Representatives in the 2026 midterm elections. The midterm elections will take place on November 4, 2026.
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/).Trader consensus heavily favors the Democratic Party at 88.5% implied probability to win California's 21st Congressional District House seat, driven by incumbent Jim Costa's strong reelection bid and proven track record in the Central Valley district. Recent mid-decade redistricting, finalized in early March 2026, has preserved Costa's favorable terrain despite forcing candidate scrambles statewide, with no major Republican challenger emerging to threaten his hold. While GOP candidates like Fresno businessman Kyle Kirkland and Lorenzo Rios announced candidacies late last year, they show limited fundraising or polling momentum ahead of the June 2 top-two primary. Incumbency advantage, district fundamentals, and Costa's moderate appeal among agricultural voters underpin the lopsided odds, though a national Republican wave or primary upset could narrow the gap.
This market will resolve according to the party of the candidate who wins the CA-21 congressional district seat in the U.S. House of Representatives in the 2026 midterm elections. The midterm elections will take place on November 4, 2026.
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/).
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, 12:08 AM ET
Volume
$0End Date
Nov 3, 2026Market Opened
Jan 28, 2026, 12:08 AM ETResolver
0x2F5e3684c...This market will resolve according to the party of the candidate who wins the CA-21 congressional district seat in the U.S. House of Representatives in the 2026 midterm elections. The midterm elections will take place on November 4, 2026.
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/).Trader consensus heavily favors the Democratic Party at 88.5% implied probability to win California's 21st Congressional District House seat, driven by incumbent Jim Costa's strong reelection bid and proven track record in the Central Valley district. Recent mid-decade redistricting, finalized in early March 2026, has preserved Costa's favorable terrain despite forcing candidate scrambles statewide, with no major Republican challenger emerging to threaten his hold. While GOP candidates like Fresno businessman Kyle Kirkland and Lorenzo Rios announced candidacies late last year, they show limited fundraising or polling momentum ahead of the June 2 top-two primary. Incumbency advantage, district fundamentals, and Costa's moderate appeal among agricultural voters underpin the lopsided odds, though a national Republican wave or primary upset could narrow the gap.
This market will resolve according to the party of the candidate who wins the CA-21 congressional district seat in the U.S. House of Representatives in the 2026 midterm elections. The midterm elections will take place on November 4, 2026.
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/).
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/).
Volume
$0End Date
Nov 3, 2026Market Opened
Jan 28, 2026, 12:08 AM ETResolver
0x2F5e3684c...Trader consensus heavily favors the Democratic Party at 88.5% implied probability to win California's 21st Congressional District House seat, driven by incumbent Jim Costa's strong reelection bid and proven track record in the Central Valley district. Recent mid-decade redistricting, finalized in early March 2026, has preserved Costa's favorable terrain despite forcing candidate scrambles statewide, with no major Republican challenger emerging to threaten his hold. While GOP candidates like Fresno businessman Kyle Kirkland and Lorenzo Rios announced candidacies late last year, they show limited fundraising or polling momentum ahead of the June 2 top-two primary. Incumbency advantage, district fundamentals, and Costa's moderate appeal among agricultural voters underpin the lopsided odds, though a national Republican wave or primary upset could narrow the gap.
Experimental AI-generated summary referencing Polymarket data · Updated
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