Betting on the NFL is set to reach new heights this season with an estimated $35 billion potentially wagered on the most popular league at U.S. sportsbooks, according to the American Gaming Association.

The American Gaming Association says the $35 billion estimate is a roughly 30% increase from the amount bet on the NFL last year and is based on data released by some states on the amount wagered on pro football. The Colorado Division of Gaming, for example, reported $890.3 million was bet on "pro American football" in the 2023/2024 fiscal year.

Three states -- Maine, North Carolina and Vermont -- have launched legal online betting markets since last NFL season. Overall, 38 states and the District of Columbia have legal betting markets entering the NFL season.

Bookmakers say, on a per-game basis, more bets are placed and more money is wagered on the NFL than on any other league. The NFL also attracts the largest bets, with six- and seven-figure bets reported nearly weekly by U.S. sportsbooks.

"The NFL typically yields the largest bets due to not only the popularity of the league, but also the schedule," Johnny Avello, sportsbook director for DraftKings, told ESPN in an email. "Standalone games tend to attract more sizable bets, and the NFL has more isolated games in the regular season than any other league. This creates a lot of excitement and draws plenty of notable bets."

The pregame point spread remains the most popular betting option on the NFL, along with the money line (odds on winning the game) and over/under total, according to sportsbooks. Christian Cipollini, trading manager for BetMGM sportsbooks, said the point spread, money line and over/under total account for approximately 50% of bets on an NFL game, with prop bets, both team and player, along with alternate markets accounting for the other 50%. Cipollini estimates that "60-65%" of NFL bets are made before kickoff but added that "Live betting is growing."

The odds to win the Super Bowl attract more betting interest annually than any other league championships. BetMGM said that it has taken twice as many bets on the winner of this year's Super Bowl as it has on the World Series. DraftKings also said the Super Bowl leads the way in terms of betting interest.

"This is a testament to the NFL's popularity, and ability keep fans and bettors engaged all year round," Avello said.

The NFL season kicks off Thursday, with the Super Bowl champion Kansas City Chiefs hosting the Baltimore Ravens.