Trump’s Election Odds Spike On Polymarket As Musk Touts Betting Site

Topline

Odds on one notable presidential election betting platform shifted majorly in former President Donald Trump’s favor Monday, much to the delight of the world’s richest man Elon Musk, though odd movements on other sites offering wagers were far less drastic.

Key Facts

Trump’s lead on Vice President Kamala Harris expanded rapidly Monday on the blockchain-based Polymarket, which allows users to place unconventional wagers on events like the presidential election.

Polymarket priced in a 53.3% chance of a Trump win and 46.1% of a Harris victory shortly after 6 p.m. EDT, up from 50.9% to 48.2% split in Trump’s favor as recently as 9:30 a.m., extending Trump’s Polymarket odds to their highest level since early August—shortly after Harris took over the Democratic nomination from President Joe Biden.

The Polymarket shift caused Trump to advance past Harris as the favored candidate by betting markets for the first time since Sept. 10, according to Election Betting Odds, which aggregates victory probabilities implied by presidential election betting platforms including Polymarket.

But Polymarket competitors moved far less Monday, as PredictIt favored Harris over Trump at what equates to a 51.4% to 48.6% margin, roughly flat over the last 24 hours, and Kalshi odds sat flat at 51% to 49% in Harris’ favor.

What We Don’t Know

What caused the swing in Trump’s favor on Polymarket. Some social media users noted the movement came as one anonymous user by the name “Fredi9999” upped his bets on a Trump win to over $4 million. Polymarket does not limit individual bettors like PredictIt ($850 limit) or Kalshi (previously $25,000 but Kalshi shared a bet of more than $60,000 on Trump Monday) as it operates as an “offshore” book and does not face the same federal regulations. So, it’s possible that Trump’s odds shifted on Polymarket as it was the result of buying activity from one or a handful of big-ticket bettors rather than a material shift in the election landscape.

Tangent

Musk, who endorsed Trump in July and appeared at a rally with the Republican candidate Saturday, shared several posts on his X social media platform touting the Polymarket shift. Musk shared a post connecting the jump to his appearance at Trump’s Pennsylvania rally, wrote betting odds are “more accurate than polls as actual money is on the line” and reposted a screenshot emphasizing the “collapse” of Harris’ election odds.

Surprising Fact

In a Monday evening post on his Silver Bulletin blog, statistician Nate Silver noted the shift in Trump’s favor on Polymarket is a “larger swing than is justified”—pointing out that his election model shows Harris with a 54.7% chance of winning. Silver, who also serves as an advisor to Polymarket, added there “isn’t much” driving the tilt, but named several theories, such as trigger-happy traders, Musk’s hype and that Polymarket’s trader base may more heavily consist of Trump supporters.

Contra

National polls show Harris holds a slight lead over Trump, and FiveThirtyEight puts Harris’ odds of securing enough electoral votes for a victory at 55%.

Crucial Quote

“Polymarket effectively takes what otherwise would be an Internet yelling match and turns that into a market where the person who's right wins,” Polymarket founder Shayne Coplan told Forbes in July.

Further Reading

CORRECTION (10/7): This story has been updated to reflect Kalshi’s betting limit.