Thirty eight million American adults, 15 percent of the U.S. adult populationare planning to bet on National Football League (NFL) games this season, according to a new survey by the American Gaming Association.

The rapid expansion of legal sports betting has provided increased opportunity for millions of Americans to bet safely with a licensed, regulated sportsbook. This year, 7 million Americans say they will bet legally at a casino sportsbook, 1.2 million more than last year, and tens of millions of others will place bets with friends, participate in pools or squares contests or place their bets online.

“During this centennial NFL season, more Americans than ever before can wager on football in safe, well-regulated environments,”said Bill Miller, AGA’s president and chief executive officer. “It is clear that as jurisdictions enact policies to provide a legal alternative to the dangerous illegal market, consumers follow suit and seek the protections they deserve.”

The survey, conducted by Morning Consult, also found that nearly one-in-four (24%) American adults say they would place a bet on the NFL if it was legal in their state. As legal sports betting continues to expand, fan engagement with NFL games will see an impact:39 percent of avid NFL fans plan to place a bet on the NFL this season.

“Sports betting clearly impacts fans’ enthusiasm for engaging with the NFL. As the legal market grows, it is imperative for gaming and adjacent industries to focus on implementing and promoting legal sports betting responsibly to protect consumers and ensure the viability of legal markets to the continued detriment of illegal operators,” Miller added.