Rhode Island raised its bet on legalized sports gambling Tuesday, going out to bid for a company to run athletics wagering at Twin River’s casinos and making a case to lawmakers why, should the U.S. Supreme Court allow it.

Expanded gaming is essential to protect the state’s third largest revenue source.

In a request for proposals, the Rhode Island Lottery says it hopes to award an “exclusive contract to provide initial sports betting services” this year in time to potentially taking wagers at Twin River Oct. 1.

Gov. Gina Raimondo’s budget proposal for next year includes $23.5 million in new state revenue from legalized sports gambling at Twin River’s casino in Lincoln and its planned casino in Tiverton. The budget includes another $4.1 million from introducing new types of games including “stadium gaming” at Twin River.

All of this is contingent on the Supreme Court overturning, through a pending case brought by New Jersey, current prohibitions on sports gambling in all but four states. Raimondo recently said she remains confident the high court will legalize sports betting.

In the first General Assembly hearing on the gambling budget proposal Tuesday night, House Finance Committee members questioned the risk of building a state budget on a future court decision.

“It looks like a Hail Mary to me,” said Rep. Anthony Giarrusso, R-East Greenwich.

But Lottery and Department of Revenue officials said acting to allow sports gambling now is essential to protect the $872 million the state makes annually from the lottery and gambling.

“If the Supreme Court overturns, we have to have sports gambling to remain competitive,” Mark Furcolo, director of the state Department of Revenue, said. “Massachusetts has big gambling entities to run their casinos. They will be able to offer sports betting very quickly.”

While the budget proposal only applies to sports wagers made at the two brick-and-mortar Twin River locations, the RFP makes clear that Lottery officials are looking further, potentially to online sports betting.

The RFP says bidders should show “their capability to readily adapt to any future additions to authorized sports betting operations in the state including, but not limited to, remote sports betting.”

And it encourages them to submit separate proposals “that include multiple options to implement other types of sports betting in Rhode Island, if later authorized by the state including innovative and cutting edge options available as sports betting technology grows.”

The budget proposal, and a Senate bill with the same language, leaves most of the details of sports wagering in Rhode Island to be worked out.

Unlike in other states, the proposal does not set a percentage of gambling revenue that would go to the state. That will be defined through the RFP process, Furcolo said.

It’s also not clear what agreement would have to be reached between the chosen bookmaker and Twin River to operate in its casinos.

Twin River did not testify at the Finance Committee hearing and spokeswoman Patti Doyle said she did not know if the company had any intention of bidding for the sports book contract, a business it is not currently in.

Professional sports leagues, particularly Major League Baseball and the National Basketball Association, have closely watched the gambling discussion in other states and, while they did not testify Tuesday night, have lobbyists registered at the State House.

Senate President Dominick Ruggerio, lead sponsor of the Senate bill legalizing sports gambling, said Tuesday he has not been approached by the leagues yet, but understands they may be interested in a 1-percent fee on wagers involving their respective games.

In written testimony submitted to the Connecticut legislature Monday, Major League Baseball proposed a 0.25-percent fee of wagers there, strict regulations to protect against cheating and mobile wagering to clamp down on the existing black market.

A representative of DraftKings testified in favor of Rhode Island moving to online sports betting.