Incumbent Democrat Zoe Lofgren's strong performance in the June 2026 top-two primary, where she secured 54.9% of the vote against Republican Shane Lewis at 29.3%, has solidified trader expectations for a Democratic victory in California's 18th congressional district. Multiple nonpartisan forecasters rate the seat Solid or Safe Democratic, consistent with its partisan voter index and the 2024 presidential margin favoring Democrats by nearly 29 points. Lofgren's long incumbency and fundraising edge further contribute to the 96.9% implied probability for the Democratic nominee. Potential shifts could arise from unforeseen developments such as a major scandal, significant health event affecting the candidate, or an unexpected national political realignment before the November 3 general election.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedCA-18 House Election Winner
CA-18 House Election Winner
$40,034 Vol.
$40,034 Vol.
Nov 2, 2026
Democratic Party
97%
Republican Party
2%
$40,034 Vol.
$40,034 Vol.
Nov 2, 2026
Democratic Party
$20,829 Vol.
97%
Republican Party
$19,206 Vol.
2%
This market will resolve according to the party of the candidate who wins the CA-18 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/).Incumbent Democrat Zoe Lofgren's strong performance in the June 2026 top-two primary, where she secured 54.9% of the vote against Republican Shane Lewis at 29.3%, has solidified trader expectations for a Democratic victory in California's 18th congressional district. Multiple nonpartisan forecasters rate the seat Solid or Safe Democratic, consistent with its partisan voter index and the 2024 presidential margin favoring Democrats by nearly 29 points. Lofgren's long incumbency and fundraising edge further contribute to the 96.9% implied probability for the Democratic nominee. Potential shifts could arise from unforeseen developments such as a major scandal, significant health event affecting the candidate, or an unexpected national political realignment before the November 3 general election.
This market will resolve according to the party of the candidate who wins the CA-18 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/).
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
$40,034End 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-18 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/).Incumbent Democrat Zoe Lofgren's strong performance in the June 2026 top-two primary, where she secured 54.9% of the vote against Republican Shane Lewis at 29.3%, has solidified trader expectations for a Democratic victory in California's 18th congressional district. Multiple nonpartisan forecasters rate the seat Solid or Safe Democratic, consistent with its partisan voter index and the 2024 presidential margin favoring Democrats by nearly 29 points. Lofgren's long incumbency and fundraising edge further contribute to the 96.9% implied probability for the Democratic nominee. Potential shifts could arise from unforeseen developments such as a major scandal, significant health event affecting the candidate, or an unexpected national political realignment before the November 3 general election.
This market will resolve according to the party of the candidate who wins the CA-18 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/).
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
$40,034End Date
Nov 3, 2026Market Opened
Jan 28, 2026, 12:08 AM ETResolver
0x2F5e3684c...Incumbent Democrat Zoe Lofgren's strong performance in the June 2026 top-two primary, where she secured 54.9% of the vote against Republican Shane Lewis at 29.3%, has solidified trader expectations for a Democratic victory in California's 18th congressional district. Multiple nonpartisan forecasters rate the seat Solid or Safe Democratic, consistent with its partisan voter index and the 2024 presidential margin favoring Democrats by nearly 29 points. Lofgren's long incumbency and fundraising edge further contribute to the 96.9% implied probability for the Democratic nominee. Potential shifts could arise from unforeseen developments such as a major scandal, significant health event affecting the candidate, or an unexpected national political realignment before the November 3 general election.
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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