Silver Bulletin author Nate Silver wrote Sunday that the FLIPR forecast gives Democrats a three-in-four chance of winning the U.S. Senate, compared with Polymarket’s two-in-three, as their estimates draw closer.
The forecast credit lists Nate Silver and Eli McKown-Dawson. Silver described the gap as noticeable but not a major disagreement. FLIPR produces a daily projection using rules set months earlier, he wrote, while Polymarket is a prediction market.
Silver said the two measures differed more on the Senate than on the House, where he saw little distance between their forecasts and viewed Democratic gains as highly likely. Democrats need four net Senate gains to take control, according to EconoTimes’ earlier account of the Senate map. The chamberwide figures do not identify which individual contests could supply those gains.
In recent days, Polymarket’s estimate moved toward Democrats, Silver wrote. FLIPR changed little over the same stretch and dipped slightly in its latest updates.
Earlier in the campaign, both measures rose after Labor Day and remained close until around Sept. 22. FLIPR’s estimate then improved further for Democrats, while Polymarket’s rise stalled. Silver said FLIPR may have moved ahead of the market by a couple of days during their earlier stretch of similar movement, though he presented that as his reading of the trend.
Polymarket’s estimate also rose around FLIPR’s Aug. 11 launch. Silver said he could not recall a major Democratic news or polling development on that date and suggested the market may have reacted to the forecast’s debut.
Silver said fixed assumptions give FLIPR a consistent daily reference as pollsters and election-rating groups revise their views during the campaign. He said he would next examine individual Senate races after comparing the overall forecasts.
