The Polymarket 'whale' betting on a Trump win is down $3 million after Harris' odds jumped over the weekend

• The Polymarket "whale" betting on a Trump win had about $3 million in unrealized losses Monday morning.
• The closely watched bettor had over $10 million in gains before Trump's odds declined last week.

The "whale" placing big bets on Polymarket for Doland Trump to win the presidential election is in the red after betting odds shifted toward Kamala Harris' over the weekend.

According to data from Polymarket and compiled by Business Insider, the anonymous election bettor, who was recently revealed to be a trader from France, had about $3 million in unrealized losses on Monday morning across his four known accounts.

The bettor's unrealized gains and losses have seen volatile swings in the past week, accelerated by a shock poll from Iowa released over the weekend that had Kamala Harris ahead of the former president in the reliably red state.

The Polymarket whale had unrealized gains of about $10 million toward the end of October before Trump's betting odds began to sink.

The Polymarket account Theo4, one of four controlled by the whale, had the biggest loss across all of its bets, at a cumulative $2.5 million loss as of Monday morning.

Much speculation has swirled about the identity and motivation of the person behind the accounts, with a number of theories floated in recent weeks about what might be going on.

However, in a report from The Wall Street Journal, which made contact with the Polymarket whale, the person said the bets are simply a high-conviction view on the outcome of the election.

"My intent is just making money," the man, who goes by Théo, said on a Zoom call with reporters from The Journal last week.

"I have absolutely no political agenda," Théo said in an email to The Journal.

Théo could see an $80 million payday if Trump wins the election, or he could lose all of the $30 million he has placed in various bets if Harris wins.

The Journal noted that the person is stuck in the trades due to the massive size of his bets and the relatively low liquidity of the market.

According to data from Polymarket, Théo controls about 25% of the contracts for Trump to win the Electoral College and more than 40% of the contracts for Trump to win the popular vote.

If Théo were to liquidate those contracts before the election on Tuesday, he'd likely be unable to sell all of his positions at current prices, as too much selling pressure could push the price of the contracts substantially lower.

For example, a hypothetical sale of Théo's 47 million shares for Trump to win the election would execute at an estimated average price of just $0.02, according to Polymarket, which would represent a 96% loss for the trader. Théo paid an average price of about $0.56 cents for the 47 million shares.

Meanwhile, a hypothetical sale of Théo's nearly 20 million shares for Trump to win the popular vote would execute at an average price of less than a 10th of a penny, according to Polymarket, representing a near-total loss.

With so much money on the line, Théo said he is feeling nervous, though he believes Trump has an 80%-90% chance to win the election.

"A surprise can always occur," Théo told The Journal.