The return of professional sports in August released pent up demand for betting on sporting events. Yesterday, New Jersey sportsbooks reported $668 million in wagers for the month, a record for any state with legalized sports betting, including Nevada, where it's been legal to bet on sports for decades.

With the state's casinos operating with limited capacity, the big winners were the online sportsbooks, which took in 90% of August's handle (the handle is how much bettors wager; revenue is how much the gaming companies keep).

FanDuel and DraftKings (DKNG -2.69%) continued to dominate the sportsbooks, generating revenue of $17.6 million and $10 million, respectively. The next closest sportsbook was MGM Resorts International's (MGM -5.01%) BetMGM and Borgata Sports platforms, with less than $3.3 million.

Sports betting app on smartphone

Image source: Getty Images.

Odds-on favorite for growth

"New Jersey's sports betting market has proven resilient since the pandemic began, drawing more bettor interest since March than any other U.S. jurisdiction," lead analyst Dustin Gouker said in a statement. "With major sports back on the board, though, the state's sportsbooks are showing shocking strength."

While New Jersey's Division of Gaming Enforcement reported total gambling revenue was down 29% year to date to $1.6 billion compared to the same period last year, internet gaming win -- or the amount gaming houses kept on all forms of online gambling versus how much was bet -- doubled to $598 million.

Online casinos and poker rooms also posted records for the month.

New Jersey's sportsbook handle jumped over 127% in August compared to the year-ago period and continues to benefit from its proximity to the New York professional sports market. It helps explain why FanDuel, which is affiliated with the Meadowlands racetrack in East Rutherford, just outside of New York City, continues to lead.