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- Société Générale is actively using prediction market pricing from Kalshi and Polymarket in its U.S. midterm election forecasting model.
- The bank’s model currently assigns Democrats a 44% chance of winning both chambers and a 43.3% chance of split control.
Société Générale’s latest U.S. midterm model says Democrats are strongly positioned to win the House, while the Senate remains a toss-up, with the bank using prices from Kalshi and Polymarket alongside polling and analyst ratings.
That makes the update notable for election-market readers as well as political watchers: a major bank is explicitly folding prediction market pricing into its congressional forecast ahead of the Nov. 3 midterms.
The model assigns a 44% chance that Democrats win both chambers and a 43.3% chance of a split result in which Democrats take the House but Republicans keep the Senate. Most of the remaining probability reflects Republicans holding unified control.
All 435 House seats and 35 Senate seats are up this cycle. Republicans currently hold a 218-214 edge in the House and a 53-47 majority in the Senate. Democrats need a net gain of three House seats and four Senate seats to take control of both chambers, according to the article.
Prediction market prices are part of the model
According to the report, Société Générale combines analyst ratings, polling and prediction market prices in its election model. It specifically cites Kalshi and Polymarket as inputs.
The article says polls receive more weight as Election Day gets closer, while the influence of prediction markets depends in part on contract liquidity. That matters for readers following election betting markets because it shows how market pricing is being treated as one signal rather than a standalone forecast.
Recent national polling cited in the article also points to Democratic momentum. A New York Times/Siena College generic ballot poll showed Democrats ahead by 8 points, while an Economist/YouGov survey put the lead at 12 points.
Senate battlegrounds could decide the market view
The bank’s model focuses on nine competitive Senate races: Alaska, Georgia, Iowa, Maine, Michigan, New Hampshire, North Carolina, Ohio and Texas.
Texas is described as one of the country’s most expensive Senate contests, with Republican groups committing more than $50 million to back Ken Paxton against Democrat James Talarico. Alaska is framed as an unexpected battleground, where former Democratic Rep. Mary Peltola is challenging Republican Sen. Dan Sullivan. The article notes Democrats have not won a Senate election in Alaska since 2008.
Société Générale said control of Congress could shape fiscal policy, oversight, government funding fights and debt-limit negotiations. The article also says a Democratic House paired with a Republican Senate would still preserve the administration’s ability to confirm nominees, while trade policy would remain largely under executive control.
The bank plans to update the model weekly through the midterms, giving election-market traders and political observers a regular read on how polling and prediction market pricing are shifting before Election Day.
Source: As reported by tradingview.com.
