Will Jamie Joyce win the 2026 12th California Congressional district race?

Question

Resolution criteria

This market resolves to YES if Jamie Joyce wins the general election for California's 12th Congressional District in the November 3, 2026, election.

This market resolves to NO if Jamie Joyce does not win the election (e.g., if incumbent Lateefah Simon wins, or if any other candidate wins). If Joyce withdraws, is disqualified, or does not appear on the general election ballot, the market resolves to NO (unless the certified winner is indeed Joyce).

The primary source of truth for resolution will be the official election results certified by the California Secretary of State. If the race is mathematically decided and uncontested, the market may resolve early based on projections from the Associated Press or other major media outlets.

Background

District Information: California’s 12th Congressional District covers the East Bay area (including Oakland, Berkeley, Alameda, and Emeryville). With a Cook Partisan Voter Index of D+39, it is historically one of the most solidly Democratic districts in the nation.

The Candidates: Challenger Jamie Joyce is a tech policy researcher, democracy tech activist, and founder of the non-profit Society Library. She is facing Democratic incumbent Lateefah Simon, who has held the seat since January 2025.

Primary Results: In California's nonpartisan top-two primary held on June 2, 2026, Simon and Joyce were the only candidates on the ballot, meaning both advanced to the general election. Simon finished first in the primary with approximately 84.4% of the vote, and Joyce finished second with approximately 15.6%.

I made this market in response to seeing this post: https://www.lesswrong.com/posts/RPsgjBsAbAuRQegjm/nunosempere-s-shortform?commentId=XyrDGDefBuicHqq47 . Seems like she was very funding-constrained and if that changes it could become a closer race than in the primary.

Manifold Markets · Answer

Almost certainly not — Manifold Markets prediction market estimates a 4% chance (17 traders, as of Sep 11, 2026).