A massive government spending bill that Congress is expected to consider this week could include a provision exempting Minor League Baseball players from federal labor laws, according to three congressional officials familiar with the talks.

The exemption would represent the culmination of more than two years of lobbying by Major League Baseball, which has sought to preempt a spate of lawsuits that have been filed by minor leaguers alleging they have been illegally underpaid.

The league has long claimed exemptions for seasonal employees and apprenticeships, allowing its clubs to pay players as little as $1,100 a month, well under the pay that would be dictated under federal minimum wage and overtime standards. But with those exemptions under legal challenge, Major League Baseball has paid lobbyists hundreds of thousands of dollars to write a specific exemption into the law.

The provision does not appear in any of the draft spending bills assembled by the House and Senate appropriations subcommittees that deal with labor matters. But the officials familiar with the negotiations, who spoke on the condition of anonymity because of the sensitivity of the talks, said the issue is under serious consideration by top party leaders.

The $1.3 trillion spending bill is expected to be released as soon as Monday evening and must pass ahead of a March 23 deadline to avoid a government shutdown. Two of the officials said that Senate Majority Leader Mitch McConnell (R-Ky.), an avid Washington Nationals fan, is among those backing the provision, although all three said leaders of both parties have been willing to entertain the measure.

Spokesmen for McConnell, Senate Minority Leader Charles E. Schumer (D-N.Y.), House Speaker Paul D. Ryan (R-Wis.) and House Minority Leader Nancy Pelosi (D-Calif.) all declined to comment.

A request for comment sent to Major League Baseball on Sunday was answered by Pat O’Conner, the president of Minor League Baseball, a separate organization that contracts with the major leagues. Minor league players are paid under contracts signed with major league teams.

O’Conner said the litigation underway represents an existential threat to minor league clubs, which could see their business model upended if courts rule that players must be paid according to the federal Fair Labor Standards Act.

“We’re not saying that it shouldn’t go up,” he said. “We’re just saying that the formula of minimum wage and overtime is so incalculable. I would hate to think that a prospect is told, ‘You got to go home because you’re out of hours, you can’t have any extra batting practice.’ It’s those kinds of things. It’s not like factory work. It’s not like work where you can punch a time clock and management can project how many hours they’re going to have to pay for.”

But Garrett R. Broshuis, a St. Louis lawyer representing a group of players who have alleged violations of federal wage and hour laws, said congressional action would deny players their basic rights.

“This is about billionaire owners using their clout to try to pass something that isn’t going through the normal procedures of legislature and that is only going to make thousands of minor leaguers suffer even more,” he said. “We’re just talking about basic minimum wage laws here — the same laws that McDonald’s has to comply with, the same laws that Walmart has to comply with. And so surely if Walmart or McDonald’s can find a way to comply with those laws, then Major League Baseball can find a way to comply with them, too.”

The lawsuit Broshuis is involved in is under litigation in the U.S. Court of Appeals for the 9th Circuit. A similar lawsuit challenging minor league compensation on antitrust grounds was dismissed by that court in June.

The Save America’s Pastime Act, a stand-alone bill granting the exemption for minor leaguers, was introduced in the House in 2016 but received no consideration. But lobbyists continued to push for the legislation. In 2017, an MLB executive and the Duberstein Group, a prominent public affairs firm retained by the league, reported lobbying the House and the Senate on the issue.

Minor League Baseball also reported lobbying for the exemption, albeit spending a fraction as much. O’Conner said that he has met with several lawmakers, including Schumer, since the push for the carve-out began and that he has won bipartisan support.

“We’re in 42 states, 160 cities. We’ve got over $3 billion of infrastructure, much of which is still being paid off by the clubs and the communities where they exist,” he said. “This is about constituents, this is about jobs at home, and this is about quality of life at home.”