According to The New York Times, Vanderbilt University researchers discovered that a Polymarket user placed a nearly $200,000 bet on October 31 that Nebraska Senator Pete Ricketts would win reelection. Approximately one hour later, a New York Times and Siena College joint poll showed Ricketts leading. The user's profits exceeded $77,000.
Researchers at Vanderbilt's National Security Institute stated that the sequence of events is difficult to view as random and warrants further investigation. Polymarket said it has identified the relevant trades and is investigating; Kalshi declined to comment. The user also placed similar large bets on other markets including Kalshi.