**Incumbent Democrat Jim Costa and Republican challenger Kyle Kirkland advanced from the June 2026 top-two primary to contest the November 3 general election in California's 21st congressional district.** The seat carries a D+5 Partisan Voter Index and is rated Likely Democratic by forecasters including the Cook Political Report and Sabato's Crystal Ball, reflecting its modest Democratic lean from recent presidential results and Central Valley demographics. Trader pricing across margin brackets remains tightly clustered near 49-50% because the expected victory margin sits in a narrow, uncertain band. Costa benefits from incumbency, established fundraising, and district trends, yet Kirkland consolidated Republican support after the primary and can draw on national midterm dynamics that have historically pressured incumbents. Limited public polling since June and the absence of major late-breaking events have kept assessments balanced between a low-single-digit Democratic win and a slightly wider one. Key factors that could widen separation include shifts in national House polling averages, candidate-specific fundraising or endorsement surges, turnout patterns in Fresno and Tulare counties, or campaign events that highlight local issues such as agriculture policy and border security. The race's structural competitiveness leaves room for modest movement in either direction before Election Day.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedRepublican 5%+ 47%
Democrat 25%+ 46%
Democrat 10-15% 46%
Democrat 5-10% 46%
NEW
NEW
Nov 3, 2026
Democrat 25%+
46%
Democrat 20-25%
45%
Democrat 15-20%
45%
Democrat 10-15%
46%
Democrat 5-10%
46%
Democrat 0-5%
45%
Republican 0-5%
45%
Republican 5%+
47%
Republican 5%+ 47%
Democrat 25%+ 46%
Democrat 10-15% 46%
Democrat 5-10% 46%
NEW
NEW
Nov 3, 2026
Democrat 25%+
$0 Vol.
46%
Democrat 20-25%
$0 Vol.
45%
Democrat 15-20%
$0 Vol.
45%
Democrat 10-15%
$0 Vol.
46%
Democrat 5-10%
$0 Vol.
46%
Democrat 0-5%
$0 Vol.
45%
Republican 0-5%
$0 Vol.
45%
Republican 5%+
$0 Vol.
47%
The 2026 CA-21 House election is currently expected to be held on November 3, 2026.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.**Incumbent Democrat Jim Costa and Republican challenger Kyle Kirkland advanced from the June 2026 top-two primary to contest the November 3 general election in California's 21st congressional district.** The seat carries a D+5 Partisan Voter Index and is rated Likely Democratic by forecasters including the Cook Political Report and Sabato's Crystal Ball, reflecting its modest Democratic lean from recent presidential results and Central Valley demographics.
Trader pricing across margin brackets remains tightly clustered near 49-50% because the expected victory margin sits in a narrow, uncertain band. Costa benefits from incumbency, established fundraising, and district trends, yet Kirkland consolidated Republican support after the primary and can draw on national midterm dynamics that have historically pressured incumbents. Limited public polling since June and the absence of major late-breaking events have kept assessments balanced between a low-single-digit Democratic win and a slightly wider one.
Key factors that could widen separation include shifts in national House polling averages, candidate-specific fundraising or endorsement surges, turnout patterns in Fresno and Tulare counties, or campaign events that highlight local issues such as agriculture policy and border security. The race's structural competitiveness leaves room for modest movement in either direction before Election Day.
The 2026 CA-21 House election is currently expected to be held on November 3, 2026.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.
Market Opened: Sep 2, 2026, 3:32 PM ET
Volume
$0End Date
Nov 3, 2026Market Opened
Sep 2, 2026, 3:32 PM ETResolver
0x69c47De9D...The 2026 CA-21 House election is currently expected to be held on November 3, 2026.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.**Incumbent Democrat Jim Costa and Republican challenger Kyle Kirkland advanced from the June 2026 top-two primary to contest the November 3 general election in California's 21st congressional district.** The seat carries a D+5 Partisan Voter Index and is rated Likely Democratic by forecasters including the Cook Political Report and Sabato's Crystal Ball, reflecting its modest Democratic lean from recent presidential results and Central Valley demographics.
Trader pricing across margin brackets remains tightly clustered near 49-50% because the expected victory margin sits in a narrow, uncertain band. Costa benefits from incumbency, established fundraising, and district trends, yet Kirkland consolidated Republican support after the primary and can draw on national midterm dynamics that have historically pressured incumbents. Limited public polling since June and the absence of major late-breaking events have kept assessments balanced between a low-single-digit Democratic win and a slightly wider one.
Key factors that could widen separation include shifts in national House polling averages, candidate-specific fundraising or endorsement surges, turnout patterns in Fresno and Tulare counties, or campaign events that highlight local issues such as agriculture policy and border security. The race's structural competitiveness leaves room for modest movement in either direction before Election Day.
The 2026 CA-21 House election is currently expected to be held on November 3, 2026.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.
This market will resolve according to the margin of victory between the top two candidates in the specified election.
The "margin of victory" is defined as the absolute difference between the percentages of valid votes received by the first-place and second-place candidates. Percentages of the valid votes received by each candidate will be determined by dividing the total number of valid votes each of the top two candidates receives by the sum of all valid votes cast in the election.
The options for "Democrat" and "Republican" refer to any representative of the Democratic Party and Republican Party, respectively, appearing on the general election ballot.
If the reported value falls exactly between two brackets, then this market will resolve to the higher margin bracket.
If two or more candidates tie for the most valid votes in this election, and the tie is between two candidates listed, this market will resolve to the lowest margin bracket for the candidate whose ballot-listed last name comes first in alphabetical order. If the tie is between a listed candidate and an unlisted candidate, this market will resolve to the lowest margin bracket for the listed candidate. If the tie is between two or more unlisted candidates, this market will resolve to "Other." If the listed candidate is represented in this market group as "Republican" or "Democrat" their ballot-listed last name will still be used for tiebreaking.
This market will resolve based on the official vote count once the count has been made official.
If the election results are not known definitively by June 30, 2027, 11:59 PM ET, this market will resolve to "Other".
If a recount is initiated before the vote total has been made official, the market will remain open until the recount is completed and the vote is made official.
The primary resolution source for this market will be the official results of the 2026 CA-21 House election as published by the state electoral authority responsible for certifying the results of the election; however, an overwhelming consensus of credible reporting may also be used.
Volume
$0End Date
Nov 3, 2026Market Opened
Sep 2, 2026, 3:32 PM ETResolver
0x69c47De9D...**Incumbent Democrat Jim Costa and Republican challenger Kyle Kirkland advanced from the June 2026 top-two primary to contest the November 3 general election in California's 21st congressional district.** The seat carries a D+5 Partisan Voter Index and is rated Likely Democratic by forecasters including the Cook Political Report and Sabato's Crystal Ball, reflecting its modest Democratic lean from recent presidential results and Central Valley demographics. Trader pricing across margin brackets remains tightly clustered near 49-50% because the expected victory margin sits in a narrow, uncertain band. Costa benefits from incumbency, established fundraising, and district trends, yet Kirkland consolidated Republican support after the primary and can draw on national midterm dynamics that have historically pressured incumbents. Limited public polling since June and the absence of major late-breaking events have kept assessments balanced between a low-single-digit Democratic win and a slightly wider one. Key factors that could widen separation include shifts in national House polling averages, candidate-specific fundraising or endorsement surges, turnout patterns in Fresno and Tulare counties, or campaign events that highlight local issues such as agriculture policy and border security. The race's structural competitiveness leaves room for modest movement in either direction before Election Day.
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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