LOUISVILLE, Ky. — Gov. Andy Beshear, D-Ky., plunked down a $20 bet on two home-state college football teams — and against an arch-nemesis school — in a quick transaction signaling that legal sports wagering is off and running in the Bluegrass State.

The Democratic governor placed the first sports bet at historic Churchill Downs, home of the Kentucky Derby, fulfilling a pledge that his administration would launch sports wagering in time for the NFL regular season.

“This is entertainment,” Beshear said. “It’s what Kentuckians were looking for. It’s going to boost tourism. It’s going to make sure we don’t lose that many people to Vegas in the first couple rounds in the NCAA tournament.”

With an eye toward public approval from voters in a state election year, the governor bet that the University of Kentucky and University of Louisville football teams will win more games this season than oddsmakers predict. A third part of the $20 parlay, all of which must happen for Beshear to cash in, was that Duke — a long-running basketball rival for both Kentucky and Louisville — would win fewer football games than projected this season.

Any winnings from the ceremonial first sports bets placed at the track will be donated to the Louisville Sports Commission, officials said.

Sports wagering facilities opened elsewhere in the state Thursday during the first phase of the rollout. At a betting facility in Lexington, state Senate Majority Floor Leader Damon Thayer, R-Frankfort, who helped champion the sports betting legislation, placed his own wager.

“Starting today, no Kentuckian will ever have to take their hard-earned money to another state just to place a sports bet,” the Republican lawmaker said.

Mobile betting, which allows bets to be placed online using smartphones, will begin later this month.

The venture is projected to generate about $23 million in yearly revenue for the state, though some supporters predict higher amounts. Most of the revenue will go to Kentucky’s public pension system. And it will stop the siphoning of revenue to other states where Kentuckians previously placed sports bets.

Sports betting became a reality after a prolonged political fight. The state’s GOP-dominated Legislature finished work on the bill to legalize, regulate and tax sports wagering in late March during the final hours of its annual session. Beshear quickly signed the measure into law.

For some Kentuckians, the launch of sports wagering was a milestone they thought might never occur after proposals to legalize it died in previous years.

But critics of sports betting see it as an addictive form of gambling that will hurt Kentucky families. A small percentage of sports wagering tax revenue will flow into a fund to help combat problem gambling.

“This expansion of predatory gambling is a lose-lose for Kentuckians, especially for children and the vulnerable,” David Walls, executive director of The Family Foundation, said in a statement.

The U.S. Supreme Court cleared the way for legalized sports betting five years ago, and since then nearly three-fourths of the states have moved to allow it.

Wagering on horse racing is a time-honored tradition in Kentucky, which bills itself as the world’s horse capital. In recent years, the state’s horse tracks have capitalized on a newer form of gambling — slots-like historical horse racing machines that allow people to bet on randomly generated, past horse races. The games typically show video of condensed races.

Now the state has ushered in sports betting at racetracks and other track-affiliated venues.

Beshear, who pushed to legalize sports betting throughout his term, put state regulators on an accelerated timetable to put the regulations in place to oversee the new form of gambling. Kentucky’s sports wagering debut came on the same day the defending Super Bowl champion Kansas City Chiefs were hosting the Detroit Lions in the NFL’s first game of the season.

The governor, who is seeking reelection in November, could reap a political windfall from his support for legalization of sports betting. Beshear has touted its passage in making his case to voters for a second term. Beshear is being challenged by Republican Attorney General Daniel Cameron.

Cameron’s campaign tried to deflect any credit away from the incumbent governor.

“The legislature deserves the credit for moving this ball down the field. Beshear once again is trying to take credit for this victory when all he did was cheer from the sidelines,” Sean Southard, a Cameron campaign spokesman, said in a statement.

The governor countered that his office worked closely with lawmakers on the legislation.

“They all know the truth,” Beshear said in response to his GOP critics. “It’s just an election season. But why don’t we all just be happy today? Sports betting is legal in Kentucky. Let’s not play politics with it.”