For now, Las Vegas remains the American sports betting epicenter.

A record $5 billion was bet at Nevada sportsbooks in 2018, the first year with legal bookmakers operating in several states around the U.S.

Bettors bet more -- and lost more ($301 million) -- in 2018 than in any other year since Nevada Gaming Control began archiving sports betting revenue in 1988. The $301 million net win for the books smashed the record of $248.7 million set in 2017.

The amount wagered at Nevada sportsbooks has increased to record levels in each of the last nine years. Michael Lawton, senior research analyst for Nevada Gaming Control, attributed consistent growth to healthy local and national economies and the increase in popularity of in-play wagering, where bettors place bets throughout a game or event.

"The state continues to see more regional and national tourists seek out the sports book when the visit properties," Lawton told ESPN. "This can be attributed to the continued national press stories and the unique experience Nevada casinos offer for sports betting, including the Super Bowl and March Madness."

Football remained the most popular sport to bet; however, the NFL and college seasons did not go well for bettors, who staked a record $1.8 billion on football and lost a net $102.4 million, a 20.9 percent year-over-year increase. It was the second most lucrative football year for the books, trailing only 2014. Nevada books also set records in basketball and baseball winnings.

Nevada experienced the milestone year as other states began offering sports betting for the first time. A ruling from the U.S. Supreme Court last May opened a path for states outside of Nevada to get into the bookmaking business. Since the ruling, legal sportsbooks have popped up in seven additional states: Delaware, Mississippi, New Jersey, New Mexico, Rhode Island, Pennsylvania and West Virginia.

More competition is expected for Nevada in the coming years, with more than half the states currently examining if sports betting is a good fit. New Jersey sportsbooks handled $1.2 billion in bets in the six months they were open last year.

"All indications at this time are that the Nevada sports betting industry has not missed a beat," said Art Manteris, a 40-year veteran Las Vegas bookmaker and vice president of race and sports for Station Casinos. "There are a lot of factors to consider, not just betting handle, and I've seen no evidence that other states' involvement has negatively impacted us. Now, Super Bowl and March Madness will be a great indication to what's ahead."