Democratic chamber odds draw attention as stocks rise on Election Day
XTB reports the S&P 500 rose about 0.5 percent and the Nasdaq 100 about 0.9 percent on Election Day while traders watched prediction market odds for chamber control. It notes that across the last 19 election cycles the S&P 500 was never negative 120 trading days after the election, averaging a gain of about 13 percent.
U.S. stocks advanced on Election Day as traders monitored prediction-market pricing for control of Congress, according to XTB. The S&P 500 gained about 0.5 percent, while the Nasdaq 100 rose about 0.9 percent.
Chamber control in focus
XTB put prediction-market odds of Democrats winning the House at about 95 percent and the Senate at about 75 percent. Those readings indicated stronger confidence in a Democratic House victory than in a Democratic Senate victory.
The figures accompanied reporting published Nov 3, 2026, at 6:30 PM ET. They describe market expectations, not confirmed election outcomes.
Historical gains offer context
XTB also highlighted the S&P 500’s performance following the last 19 election cycles. Across that sample, the index was never negative 120 trading days after the election, with an average gain of about 13 percent.
That historical record provides context for the Election Day advance, but it does not establish that the current cycle will follow the same pattern or that chamber-control expectations caused the stock gains.
What it means for prediction markets
- The roughly 95 percent House reading and 75 percent Senate reading imply different levels of uncertainty for the two chamber-control outcomes.
- The reported odds are a snapshot of expectations around the results, rather than a statement of the eventual outcome.
- The S&P 500’s post-election history concerns equity returns; it does not independently validate the probabilities assigned to Democratic control.
Sources & attribution
- Published
- Source
- XTB
- Publisher
- The publisher did not list a web address.
- Source URL
- The feed did not publish this story's article address.
Full attribution under the Digital Millennium Copyright Act (DMCA), 17 U.S.C. § 512: this article is an original report by Infiniti Intelligence that summarizes the reporting of the publishers named above, links to their original work, and reproduces no protected expression beyond brief factual reference and in-line attribution (“according to XTB”). All rights in the underlying reporting remain with the publishers listed; nothing here implies endorsement by or affiliation with them. Rights holders may request correction, update or removal through the contact address published at infiniti.w3ai.io.
Related
- The first real move of election night lifts four Senate races at once, with Michigan's El-Sayed up to 83c
- Politics takes 40 of the 50 most-traded markets and $69M of the board's $80M in 24-hour volume into the count
- Senate control jumps to 83 percent and House control to 98 percent in the first post-close live read, with expected seats at 52.8 Democratic Senate seats and 252.1 House seats, Polyguana reports
- Alaska Senate market prices Mary Peltola at 71 percent on both Kalshi and Polymarket as the last polls in the country close at 1 a.m. ET, Action Network reports
- Iowa Senate market slips back under even money to 49 cents in the final pre-close check-in as its volume jumps from about 466,000 to about 759,000 contracts in 40 minutes, PredictionMarketPicks reports
- Polymarket conditional markets price a U.S. recession by the end of 2027 at 35 percent if Democrats sweep Congress against 19 percent if they do not, Cointelegraph reports