Overview
- Prediction markets signaled a broad Democratic sweep on Election Day, Tuesday, Nov. 3, and in many cases projected winners before major news outlets, with Polymarket saying it called 10 key races a median 31 minutes ahead of networks.
- Trading reached very large sums on Tuesday, with reports of at least $1.48 billion wagered on election markets that day and platform cycle totals reported in the billions, underscoring how much money now flows through sites such as Kalshi and Polymarket.
- The markets were mostly accurate but made notable errors, including South Carolina where Democrat Annie Andrews beat Republican Darline Graham despite markets implying roughly a 70% chance for Graham.
- Researchers and reporting show structural vulnerabilities: a small share of accounts account for a large share of volume, liquidity was thin in some markets, and platforms have recorded high‑profile misses in past contests such as Brazilian elections.
- The surge in attention and cash has accelerated newsroom partnerships and public debate, prompted pushback from forecasters like Nate Silver, and intensified regulatory scrutiny over whether these contracts operate as financial instruments or gambling.