ATLANTIC CITY — Nearly 68 million American adults — about 1 in 4 — plan to bet on this year’s Super Bowl, setting a record by a wide margin, according to the gambling industry’s national trade association.

Figures released Tuesday by the American Gaming Association include bets placed with legal outlets, as well as with illegal bookies and online operations in other countries.

The volume of betting participation is projected to be 35 percent higher than last year, which was the previous record.

Bettors plan to wager an estimated $23.1 billion on this year’s Super Bowl, up from $16 billion last year, the group predicted.

Of that, about $1.5 billion is projected to be bet with legal outlets, the group said, citing consensus estimates from various sources. That is in the same ballpark as the $1.25 billion in legal bets projected by Irvine, California-based research firm Eilers & Krejcik Gaming.

Sports betting is legal in 38 states and the Columbia District.

“There’s a good chance that every Super Bowl for the next ten or so years will be the most bet Super Bowl thanks to the underlying growth of regulated sports betting in the U.S.,” said gambling analyst Chris Grove, a partner at Eilers & Krejcik Gaming.

Sunday’s game will feature the defending Super Bowl champion Kansas City Chiefs against the San Francisco 49ers in a rare rematch from four years ago.

The 49ers are favored by 2.5 points, meaning they would have to win the game by 3 or more points for bets on them to be winners. Conversely, if the Chiefs win, or if they lose by no more than 2 points, bets on Kansas City would win. Those odds are from FanDuel Sportsbook, the official odds provider for the Associated Press.

The romance between Chiefs star tight end Travis Kelce and pop superstar Taylor Swift might be helping drive interest in this Super Bowl. About 73 percent of adults say they plan to watch the game this year, about 10 percent higher than in recent previous years.

“I think the ‘Taylor Swift effect’ will be more obviously felt in terms of the total number of people watching and betting on the game than it will be in the total dollars bet on the game,” Mr. Grove said. “But there’s little doubt that sportsbooks will be seeing Swifties sign up that otherwise would not have given sports betting a second thought.”

Likewise, a vice president with the American Gaming Association, Cait DeBaun, said Ms. Swift could be one of several reasons for increased betting on this year’s Super Bowl, along with “the compelling matchup,” the game being held at Las Vegas, the nation’s betting capital, and the growing availability of legal sports betting in the U.S.

The largest group in the survey — 42.7 million adults — plans to place a wager online (legally or illegally), at a retail sportsbook or with an illegal bookie, an increase of 41 percent from last year.

About 36.5 million adults plan to bet casually with friends, or as part of a pool or squares contest, up 32 percent from last year.

Bettors are nearly split on the outcome of the game, with 47 percent planning to bet on the Chiefs and 44 percent planning to bet on the 49ers, according to the association’s survey conducted between January 30 and February 1 of a national sample of 2,204 adults. The survey has a margin of error of plus or minus 2 percentage points.

Associated Press