MGM Resorts, the gaming operator expected to be awarded the first Massachusetts casino license by the end of May, asked gaming regulators Thursday to mitigate “the massive financial risk” it would face in launching a project that a ballot initiative could sink.

Michael Mathis, president of MGM Springfield, said that as soon as MGM was awarded the license, it would become obligated to make up-front payments of some $200 million, including an $85 million licensing fee, within 60 to 90 days.

That’s a big sum to ante up amid uncertainty surrounding casino opponents’ drive for a statewide referendum aimed at repealing the 2011 law that authorized up to three casinos and a slots parlor. Mathis told the Massachusetts Gaming Commission it could alleviate the risk by issuing MGM a “provisional” license that would become effective once the repeal effort plays out, either in court this summer or in a November referendum.

The commission, which appeared receptive to MGM’s request, deferred taking action on it.

Massachusetts Attorney General Martha Coakley blocked the Repeal the Casino Deal group last year, ruling a referendum on the expanded-gambling law would violate the state constitution. That prompted the group to appeal.

Massachusetts’ Supreme Judicial Court is scheduled to hear the group’s challenge May 5 and render a decision in July. The parties involved, including applicants for casino licenses, filed briefs this week.

Coakley’s office contends that the state has an “implied contract” with the operators seeking casino licenses and that the referendum would amount to an uncompensated taking of private property.

MGM, which plans to develop an $800 million project in Springfield, is the only remaining applicant for the one license the commission is to award for western Massachusetts. Mohegan Sun, which proposed a project in Palmer, dropped out of the running when Palmer voters rejected the plan in a referendum last November.

Mohegan Sun has since proposed a project in Revere, a city in the Greater Boston region, where it is competing for the license also sought by Wynn Resorts.