Popular online betting markets are showing a dead heat between President Trump and Vice President Harris in the race for the White House. The markets have become akin to a special poll tracked by political observers online, and the industry has already raked in more than $1 billion in bets placed for the presidential election alone. 

The three main markets watched by observers — Polymarket, PredictIt, and Kalshi — all show that bettors are nearly evenly split on the question of who will win, though one of the markets is trending in Trump’s direction at the moment.

Polymarket has shifted slightly toward Trump in recent days, now giving him a 51 percent chance of winning to Ms. Harris’s 48 percent. In the last month, his largest lead over Ms. Harris was 53 percent to 46 percent on the morning of the presidential debate, though Ms. Harris quickly took the lead in the Polymarket betting after she was widely seen as the victor in that contest. Her best day on Polymarket in the last month was on September 19, when she led Trump by a margin of 52 percent to 46 percent. 

Trump’s strength on Polymarket is driven by the bets on individual swing states, which can also be placed directly by users. In the seven battleground states that will decide the election — Nevada, Arizona, Georgia, North Carolina, Pennsylvania, Michigan, and Wisconsin — Ms. Harris leads in just three: Nevada, Michigan, and Wisconsin. Trump has strong leads in Arizona, North Carolina, and Georgia, but his eight-point lead over Ms. Harris in the Pennsylvania betting market is what is giving him the edge in the electoral college model. 

On PredictIt, Ms. Harris is still favored, though the odds have tightened since she saw a spike in support following her debate with Trump on September 10. Her high water mark of 59 cents came on September 24 — exactly two weeks after she debated the former president. Today, the cost of a “yes” share for Ms. Harris’s victory is 54 cents, compared to 50 cents for Trump. 

Kalshi uses the same methodology of allowing bettors to purchase shares in outcomes by purchasing either “yes” or “no,” though unlike PredictIt, they also provide percentages of who is most likely to win based on their users’ bets. 

The current market shows Ms. Harris with a razor-thin lead, 51 percent to 49 percent over Trump. Just over $500,000 has been bet on Kalshi on the presidential election question since the market opened on Friday morning. Kalshi says its market will officially close on election day at 10 o’clock in the morning.  

The rapid growth of these betting firms and the newfound popularity of placing bets on politics could turn the market into a multi-billion industry in the next few years. According to Statista, the total market of the sports betting industry was just over $240 billion in 2023, and political gambling could find new fans among those bettors who like to take a risk on their favorite teams. Across Polymarket, PredictIt, and Kalshi, more than $1.3 billion has been bet on the question of who will win the 2024 election. 

That doesn’t even scratch the surface of what people are betting on with respect to this year’s election. On Polymarket alone, bettors can place money on questions of who will win the House and Senate, who will win the rust belt, and who will win individual states. There are $2.7 million in bets so far on which state will be the “tipping point” that puts either Trump or Ms. Harris over 270 electoral votes.