# Will exactly 2 Senate Republican members lose their primary in 2026

> Liquidity-weighted aggregate at 94% across 1 contract — refreshed 26 min ago.

URL: https://simplefunctions.dev/odds/loseprimarysenater
Updated: 2026-06-26T07:20:50.987Z
Category: politics · Topic: election-2026
Status: active
Closes: 2026-11-03

## Headline

- Probability: 94% (liquidity-weighted across 1 contract)
- Venue: Kalshi (1 contract)
- 24h volume: $65

## Bound contracts (1)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| 2 | 94¢ | +2pp | $65 | kalshi | /markets/will-exactly-2-senate-republican-members-lose-thei-kalshi-kxloseprimarysenater-26nov03-2 |

## 30-day trajectory

| Day | Aggregate |
|---|---|
| 2026-05-27 | 89 |
| 2026-06-12 | 93 |
| 2026-06-15 | 93 |
| 2026-06-23 | 95 |

_17 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## Analysis

This market estimates a 21% chance that exactly two Senate Republicans will lose their primary elections in 2026. Primary challenges to incumbents depend on factors like district/state ideology, fundraising strength, endorsements, and candidate quality. Historical context matters: Senate Republican primary losses have been relatively rare in recent cycles, though they do occur during waves of dissatisfaction with establishment members. The probability reflects expectations that while primary challenges will happen, the specific outcome of exactly two losers is neither highly likely nor highly unlikely. Resolution requires tracking all Senate Republican primaries through the 2026 election cycle, with most contests occurring between March and September 2026. Related markets suggest uncertainty about the total number of Republican primary losses, with traders pricing lower odds for outcomes of 4+ Senate losses (9 cents) but higher odds for exactly 1 loss (29 cents), indicating a relatively flat distribution across different scenarios.

### Key factors

- Current Senate Republican incumbents facing well-funded, ideologically-motivated primary challengers and their polling performance relative to primary voters
- National political environment and any major scandals or legislative votes that might energize specific primary constituencies between now and primary season
- Endorsement patterns from Trump, state party officials, and major outside groups, which have historically influenced Republican primary outcomes
- Primary election calendar timing and field fragmentation—whether multiple challengers split anti-incumbent votes or consolidate support
- Historical baseline: Senate Republican primary defeats averaged roughly 1-2 per cycle in recent decades, making exactly 2 neither extreme nor baseline

## Methodology

Probability is **liquidity-weighted** across all bound Kalshi/Polymarket contracts: Σ(price × volume) ÷ Σ(volume). 30-day trajectory uses the daily mean of intraday 5-min captures. 24h delta = today's mean − yesterday's mean. Movement events are ≥3pp daily moves in the last 7 days.

## How to use this data

- HTML: https://simplefunctions.dev/odds/loseprimarysenater
- JSON: https://simplefunctions.dev/api/public/odds?slug=loseprimarysenater
- 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.