2026 · U.S. HOUSE · CA-21
CA-21.
What do the markets say?
California District 21 U.S. House election, 2026. Compare each source’s prices and how they have changed.
THE RACE OVER TIME
How the markets have moved
Historical prices retain each source’s metric: Kalshi daily bid/ask midpoint, Polymarket outcome price, and ForecastEx daily close. Gemini and PredictIt show stored daily bid/ask observations where older provider history is unavailable. ForecastEx file dates use a 12:00 UTC display anchor. Lines join available observations; missing dates are not filled.
Accessible chart data
| Source | Party | UTC time | Price |
|---|
What each market says
INDEPENDENT CONTRACTS · NO AVERAGINGThe same race can have different resolution rules across sources. Each price below belongs to its own contract.
Kalshi
Source updated 9/15/2026, 5:15:06 PM ET
View contract at Kalshi ↗Question, identity & settlement rules
Will a Democrat win the House race for CA-21?
HOUSECA21-26-DIf the House member sworn in for CA-21 for the term beginning in 2027 is a member of the Democratic Party, then the market resolves to Yes.
Source updated 10/16/2026, 12:31:24 PM ET
View contract at Kalshi ↗Question, identity & settlement rules
Will a Republican win the House race for CA-21?
HOUSECA21-26-RIf the House member sworn in for CA-21 for the term beginning in 2027 is a member of the Republican Party, then the market resolves to Yes.
Polymarket
Source updated 10/25/2026, 5:30:37 PM ET
View contract at Polymarket ↗Question, identity & settlement rules
Will the Republican Party win the CA-21 House seat?
1281076:0This 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 3, 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/).
Source updated 10/25/2026, 5:22:37 PM ET
View contract at Polymarket ↗Question, identity & settlement rules
Will the Democratic Party win the CA-21 House seat?
1281077:0This 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 3, 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/).
ForecastEx
No verified contract for this race from ForecastEx.
Gemini
YES bid/ask midpoint · daily observation
Collected during the scheduled daily refresh
View contract at Gemini ↗Question, identity & settlement rules
California District 21 U.S. House election, 2026
GEMI-HOUSE26CA-21-JIMCOSTAIf Jim Costa wins the 2026 U.S. House election in CA-21, then this market resolves to Yes. Outcome should be verified from the applicable state election authority and widely reported national sources. View the [full rules](https://cdn.builder.io/o/assets%2F1b77ce3a269a43e985e77f3d65f715ba%2F8634b5141fe14d6783a347884150d6bd?alt=media&token=f103a20d-e51f-47f5-ad36-03aaaafec1cc&apiKey=1b77ce3a269a43e985e77f3d65f715ba).
YES bid/ask midpoint · daily observation
Collected during the scheduled daily refresh
View contract at Gemini ↗Question, identity & settlement rules
California District 21 U.S. House election, 2026
GEMI-HOUSE26CA-21-KYLEKIRKLANDIf Kyle Kirkland wins the 2026 U.S. House election in CA-21, then this market resolves to Yes. Outcome should be verified from the applicable state election authority and widely reported national sources. View the [full rules](https://cdn.builder.io/o/assets%2F1b77ce3a269a43e985e77f3d65f715ba%2F8634b5141fe14d6783a347884150d6bd?alt=media&token=f103a20d-e51f-47f5-ad36-03aaaafec1cc&apiKey=1b77ce3a269a43e985e77f3d65f715ba).
PredictIt
No verified contract for this race from PredictIt.
Reading the California election markets
These prices describe contracts about the california district 21 u.s. house election, 2026, rather than the share of voters supporting a party. A 60% contract price is not a prediction of a 60% vote share.
Kalshi, Gemini and PredictIt use valid YES bid/ask midpoints. Polymarket uses its outcome-price feed. ForecastEx uses the most recently published daily closing price; its file date is shown. We show Democratic, Republican and any verified independent contracts separately, without forcing the prices to add up to 100%.
History comes from provider time series and observations stored by 567politics. If a provider is unavailable, available stored history is labeled. Missing data stays missing.
Contract mapping checked 2026-10-25. Full methodology ↗