# CA-04 Primary Winners

> Closed. Last odds frozen 7 h ago — final outcome on the venue.

URL: https://simplefunctions.dev/odds/ca04-primary-winners
Updated: 2026-06-17T07:20:23.157Z
Category: general · Topic: election-2026
Status: historical
Closes: 2026-06-02

## Headline

- Leader: Mike Thompson at 96%
- Runner-up: Eric Jones at 92%
- Outcomes: 3 (winner-take-all)
- Venue: Polymarket (3 contracts)
- 24h volume: $297

## Bound contracts (3)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| Mike Thompson | 96¢ | ±0 | $49 | polymarket | /markets/ca-04-primary-winners-mike-thompson-polymarket-0x1972da460e8d3b6654e96ab3374003367af411c97244e25f981d1f67547c56e7 |
| Eric Jones | 92¢ | +6pp | $242 | polymarket | /markets/ca-04-primary-winners-eric-jones-polymarket-0x37e9fa09e605b87c7854ea2ae50c1f63b90f686f969a56cda41d519aa4f2d099 |
| Laurie MacKenzie | 4¢ | −3pp | $6 | polymarket | /markets/ca-04-primary-winners-laurie-mackenzie-polymarket-0xa3547b73ba1e2d690d1073d3d215175534d557d542f20a3ff18e6cb9cdc5d9aa |

## 30-day trajectory

| Day | Mike Thompson | Eric Jones | Laurie MacKenzie |
|---|---|---|---|
| 2026-05-18 | 98 | 90 | 5 |
| 2026-06-03 | 96 | 51 | 5 |
| 2026-06-07 | — | 72 | 3 |
| 2026-06-10 | — | 77 | — |
| 2026-06-16 | — | 98 | 0 |

_30 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## What moved the line

- 2026-06-12 · Eric Jones +9pp 77→86¢ · polymarket
- 2026-06-15 · Eric Jones +6pp 86→92¢ · polymarket
- 2026-06-16 · Eric Jones +6pp 92→98¢ · polymarket
- 2026-06-10 · Eric Jones +4pp 73→77¢ · polymarket
- 2026-06-13 · Eric Jones −4pp 86→82¢ · polymarket

## Analysis

This 39% probability reflects the likelihood that a specific candidate will win the California 4th Congressional District primary in 2026. The estimate sits between two different market assessments: Kalshi contracts price it at 62%, while Polymarket contracts average 35%, a substantial 27-percentage-point gap suggesting disagreement about the race outcome. The probability would likely move higher if polling shows the favored candidate gaining ground, or lower if unexpected challengers enter or if fundraising shifts materially. The primary election itself will definitively resolve this question, providing the key catalyst when California holds its primary vote in June 2026.

### Key factors

- Kalshi and Polymarket show a 27-point spread, indicating significant market disagreement that could narrow as campaign information becomes clearer
- Eric Jones appears as the leading name across multiple contracts, trading at 50¢ on Polymarket and 63-89¢ on Kalshi, suggesting he is the frontrunner though not consensus favorite
- Trading volume remains low ($96-522 per day), meaning thin liquidity could amplify price movements from new information or modest money flows
- No recent polling data or campaign finance reports are reflected in the summary, creating room for shift as 2026 progresses
- The California primary is scheduled for June 2026 and will provide definitive resolution of all related contracts

## Methodology

Headline is the **leader's price**, not an arithmetic mean — averaging disjoint winner-take-all outcomes is meaningless. Per-outcome prices come from the venue's last-traded mid; cross-venue values are simple means across contracts on each venue.

## How to use this data

- HTML: https://simplefunctions.dev/odds/ca04-primary-winners
- JSON: https://simplefunctions.dev/api/public/odds?slug=ca04-primary-winners
- Topic hub: https://simplefunctions.dev/predictions/election-2026

## License

CC-BY-4.0. Attribute "SimpleFunctions" with a link to https://simplefunctions.dev. See https://simplefunctions.dev/legal for terms.