In 2017, Nevada was the only state where bettors could wager on sporting events. A mere four years later, 21 states and the District of Columbia have legalized sports betting.

Victor Strategies Vice President Gene Johnson, who Thursday led the panel discussion “Sports Betting on the Horizon: Who’s Next” at the Indian Gaming Tradeshow & Convention in Las Vegas, said only five states are currently not considering some form of sports wagering.