NEW YORK (Reuters) - One of the four accounts on Polymarket that have fueled speculation over their large bets on a Trump election victory has taken even bigger wagers, increasing the collective potential payout if Trump wins from $30 million on Friday to nearly $43 million Monday morning, according to Polymarket's activity tracker. 

The four accounts on the cryptocurrency-prediction exchange are owned by non-Americans or a single non-American, a person familiar with the matter told Reuters on Friday, speaking on condition of anonymity.

 The bets, coming with the rise in Trump's odds on Polymarket, have drawn scrutiny because they diverge sharply from opinion polls. Polls have indicated a neck-and-neck race between Vice President Kamala Harris and former President Donald Trump. 

On Polymarket, however, Trump's chances have soared to 63% versus Harris's 37%. Odds on other prediction markets, such as Kalshi and PredictIt, have followed suit.

That has raised questions by social media users and prediction-market experts about whether large bets were swaying the markets or whether prediction markets were simply a better leading indicator.  

On Monday, Commodity Futures Trading Commission Chairman Rostin Behnam said betting on the election "puts us in a very difficult place. It makes us an election cop." 

Speaking to a Wall Street trade group, Behnam said Congress should weigh in on the permissibility of election-related betting, noting that "we don't want to put democracy and elections in jeopardy."

Polymarket shares are priced on the probability of the outcome. If Trump's chances of winning the election are trading at 60 cents, for example, it means that the market thinks there is a 60% chance of a Trump win, according to the website. If Trump wins, the buyer gets $1 per share. If Trump loses, the shares become worthless. 

Social-media users had questioned whether high-profile Americans could be behind the moves. The source confirmed to Reuters on Friday that Polymarket verifies its largest traders and the accounts were based overseas.

Reuters could not immediately determine if the four accounts - named Fredi9999, Theo4, PrincessCaro, and Michie - represent a single trader or many. Those accounts added up to holding nearly $43 million in shares in total on Monday, compared with $30 million on Friday. One share equals one dollar. 

Bettors on Polymarket have wagered $1.1 billion on the presidential race.

Polymarket, based in New York, did not respond to a request for comment on Monday regarding the increased size of the accounts.

Americans have faced steep restrictions on betting on U.S. elections online. The CFTC has previously rejected applications to offer contracts or derivatives that allow Americans to bet on elections.

The CFTC did not respond to a request for comment on Monday.