Thursday, October 15, 2026
B.C. votes in 9 days

California’s 4th District

U.S. House · CA-4

Election day November 3, 2026 · forecast of October 15, 2026

Our forecast gives the Democrats a more than 99% chance of winning, with an average lead of 27.0 points.

Safe seat. Chance of a final gap under 5 points: 1%.

Projected vote share

Projection by party

  • Democrat 63.5%
  • Republican 36.5%

Thin vertical mark: 2024 result.

Compared with the average

Democrat Republican
CA-4 63.5%36.5%
National averageUnited States 54.5%+9.0 44.2%−7.7

Simple average of the 435 districts, not weighted by population.

Projection track

How the projection has moved

Current member

Mike Thompson · Democrat

Primary results

Held June 2, 2026 · Certified official result · Official source

Top-two primary Mike Thompson · Advanced to the general election 41.0% 84,753 votes
Top-two primary Eric Jones · Advanced to the general election 22.2% 45,992 votes

Who's running

The candidates

Candidates for the upcoming election.

  • Democrat Incumbent

    Mike Thompson

    source
  • Democrat Challenger

    Eric Jones

    source

Previous election (2024)

The Republicans won by 29.3 points.

Our current projection: the Democrats ahead by 27.0 points.

Where these voters came from

This district was redrawn in the 2025-2026 redistricting. Share of its voters from each former district:

  • Former district 4 45%
  • Former district 1 40%
  • Former district 3 13%

Nearby districts

Party ahead and how sure the projection is.

  • CA-6 Democrat, safe seat
  • CA-8 Democrat, safe seat
  • CA-7 Democrat, safe seat
  • CA-1 Democrat, safe seat
  • CA-10 Democrat, safe seat
  • CA-3 Democrat, safe seat

Watch list

The tightest races

The smallest projected gaps between the top two.

  1. AZ-2Republican52%5.7-point gap
  2. KY-6Republican53%5.8-point gap
  3. VA-1Republican58%5.8-point gap
Forecast updated