Trader consensus on Republican control of the Senate after the 2026 midterms has tightened to a near coinflip, driven by seven GOP retirements—including Sens. Mitch McConnell, Thom Tillis, and Joni Ernst—opening seats in battlegrounds like North Carolina, Maine, Georgia, and Michigan. Recent U.S.-Israel strikes on Iran and President Trump's threats of further action against Iranian energy infrastructure have sparked backlash, amplifying Democratic gains in early special elections where they flipped five Republican House seats. Prediction markets reflect rising competitiveness in Ohio and Alaska despite the map's structural GOP edge, with Democrats favored in New Hampshire and Minnesota. March primaries in five states and ongoing foreign policy developments could tip odds further by March 31.
Experimental AI-generated summary referencing Polymarket data · UpdatedRepublican 2026 Senate odds hit___ by March 31?
Republican 2026 Senate odds hit___ by March 31?
$292,344 Vol.
↑ 90%
1%
↑ 80%
1%
↑ 75%
1%
↑ 70%
2%
↓ 40%
3%
$292,344 Vol.
↑ 90%
1%
↑ 80%
1%
↑ 75%
1%
↑ 70%
2%
↓ 40%
3%
A tie in the number of minutes will not suffice.
The resolution source will be the underlying minute-level price data for 'Republican Party' in the "Which party will win the Senate in 2026?" market, which can be viewed using the bar chart on https://derivative.polymarket.com/index/2026-us-senate-election-republican-odds-over-90-by-march-31 or through the “Resolution” tab with the time set to show the four-hour window. Both interfaces display the same underlying data.
Note: This market will resolve according to the price scoring methodology of derivative.polymarket.com.
Market Opened: Dec 5, 2025, 4:00 PM ET
Resolver
0x65070BE91...A tie in the number of minutes will not suffice.
The resolution source will be the underlying minute-level price data for 'Republican Party' in the "Which party will win the Senate in 2026?" market, which can be viewed using the bar chart on https://derivative.polymarket.com/index/2026-us-senate-election-republican-odds-over-90-by-march-31 or through the “Resolution” tab with the time set to show the four-hour window. Both interfaces display the same underlying data.
Note: This market will resolve according to the price scoring methodology of derivative.polymarket.com.
Resolver
0x65070BE91...Trader consensus on Republican control of the Senate after the 2026 midterms has tightened to a near coinflip, driven by seven GOP retirements—including Sens. Mitch McConnell, Thom Tillis, and Joni Ernst—opening seats in battlegrounds like North Carolina, Maine, Georgia, and Michigan. Recent U.S.-Israel strikes on Iran and President Trump's threats of further action against Iranian energy infrastructure have sparked backlash, amplifying Democratic gains in early special elections where they flipped five Republican House seats. Prediction markets reflect rising competitiveness in Ohio and Alaska despite the map's structural GOP edge, with Democrats favored in New Hampshire and Minnesota. March primaries in five states and ongoing foreign policy developments could tip odds further by March 31.
Experimental AI-generated summary referencing Polymarket data · Updated

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