GOP Senate Seats After 2026 Midterms: Odds & Probability

Prediction markets price Will the Republican Party hold 47 or fewer Senate seats after the 2026 midterm elections at 29.5%.

29.5%0.0 pts 24h

Will the Republican Party hold 47 or fewer Senate seats after the 2026 midterm elections?

Updated · Volume $2.9M

24%26%29%32%Aug 14Aug 21Aug 29Sep 5Sep 12
OutcomeProbability24h
Will the Republican Party hold 47 or fewer Senate seats after the 2026 midterm elections?29.5%0.0
Will the Republican Party hold exactly 48 Senate seats after the 2026 midterm elections?15.5%0.0
Will the Republican Party hold exactly 49 Senate seats after the 2026 midterm elections?13.5%0.0
Will the Republican Party hold exactly 50 Senate seats after the 2026 midterm elections?12.5%+0.5
Will the Republican Party hold exactly 51 Senate seats after the 2026 midterm elections?10.5%0.0
Will the Republican Party hold exactly 52 Senate seats after the 2026 midterm elections?5.9%+1.5
Will the Republican Party hold exactly 53 Senate seats after the 2026 midterm elections?5.0%+0.2
Will the Republican Party hold exactly 54 Senate seats after the 2026 midterm elections?3.6%+0.1
Will the Republican Party hold exactly 55 Senate seats after the 2026 midterm elections?1.8%-0.4
Will the Republican Party hold exactly 56 Senate seats after the 2026 midterm elections?1.4%0.0
Will the Republican Party hold 57 or more Senate seats after the 2026 midterm elections?0.8%0.0

The top 5 outcomes account for 81.7% of the total probability.

Context

Aug 11, 2026

Probability fell from 41.0% to 25.5% — a 15.5-point move over the past day.

Aug 10, 2026

Probability rose from 23.5% to 41.0% — a 17.5-point move over the past day.

This probability comes from live prices on prediction markets, where a contract's price equals the implied chance of the outcome. It updates continuously as trading occurs.

This market has 11 tracked outcomes and $2.9M in total trading volume.

The most closely contested outcome, Will the Republican Party hold 47 or fewer Senate seats after the 2026 midterm elections, is priced at 29.5%.

Data: Polymarket · Methodology · Not financial advice

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