WASHINGTON — With Republicans set to control Washington, conservative lawmakers and policy experts who could advise the next Trump administration are discussing long-sought cuts to Medicaid, the government health program that covers a fifth of all Americans and makes up about 10% of the federal budget.

Some of the changes are being proposed as a way to pay for a law that would extend the tax cuts from the first Trump administration, most of which benefited corporations and wealthier Americans. The policies might slash funding for the Affordable Care Act’s Medicaid expansion — which added about 23 million people to the program — or require that many enrollees work in order to receive benefits.

Rep. Jodey Arrington, R-Texas, who leads the House Budget Committee, told reporters this month that he favored a “responsible and reasonable work requirement” for Medicaid.

And Sen. John Cornyn, R-Texas, said of Medicaid: “We ought to look at whether we’re doing it the right way.” He said he supports “block grants,” in which states get lump sums, regardless of how many people sign up for the program.

These ideas resurrect conservative proposals going back years; they have appeared in recent House Republican budget proposals and in the high-profile policy agenda known as Project 2025. Work requirements, which struggled to get off the ground in the first Trump administration, would cut federal spending by at least $100 billion over the next decade and cause 600,000 people to lose coverage, according to estimates from the Congressional Budget Office.

“If you want to avoid a debt spiral, there have got to be reforms made to federal health programs,” said Brian Blase, a former Trump health policy adviser who now runs Paragon Health Institute, a conservative think tank. Blase has discussed Medicaid reform in recent years with conservative lawmakers and aides.

Medicaid has become deeply embedded in American life, covering nearly half of all children in the United States. It also pays for a significant portion of the nation’s nursing home care and mental health treatment. States and the federal government share the program’s costs, which totaled $880 billion in 2023.

Medicaid enrollment swelled to 87 million people under President Joe Biden, with emergency pandemic legislation that required states to keep people on the program longer than normal. Some longtime holdout states also opted into the Affordable Care Act’s Medicaid expansion, which offered the coverage to adults with family earnings up to $43,000 a year for a family of four.

That rapid growth has made the program a top target for a Republican- controlled Congress.

“It could be the most consequential year in Medicaid’s life,” said Joan Alker, a Medicaid expert who leads the Center for Children and Families at Georgetown University. Chris Pope, a senior fellow at the conservative Manhattan Institute, said Medicaid “is going to be where the action is.”

On Nov. 19, President- elect Donald Trump chose Dr. Mehmet Oz, a celebrity doctor who regularly promotes dietary supplements and other alternative health products, to lead the Centers for Medicare and Medicaid Services. Oz will “cut waste and fraud within our country’s most expensive government agency,” Trump said.

Still, Republicans could face political resistance in efforts to cut Medicaid, especially because it has so many enrollees — millions more than Medicare, the public insurance program for people over 65. In 2017, Republicans faced a major backlash for trying to roll back the Obamacare Medicaid expansion.

More than 70% of adults want Medicaid to stay largely as it is, according to a survey conducted this year by KFF, a nonprofit research group.

“If they go in and say we’re going to make big cuts and do massive policy, that will start the holy wars we saw in 2017,” said Rodney Whitlock, a vice president at McDermott+ and a former Republican Senate health aide.

Many conservatives have homed in on policies that would reduce federal funding for adults who enrolled through the Obamacare expansion. Before that, Medicaid was largely restricted to children, mothers and people with disabilities.

The federal government pays states 90% of the costs for Obamacare expansion enrollees. But over the summer, Blase published a detailed proposal for slashing that figure to as low as 40%, which could save hundreds of billions of dollars over a decade.

Faced with such a large funding reduction, some states may stop participating in the Medicaid expansion, experts said.

A Medicaid work requirement would also target adults who were added in the expansion (although most of them are already working). Congressional Republicans have repeatedly introduced laws with Medicaid work requirements but struggled to get them passed. Last spring, for example, Republicans tried attaching the policy to debt ceiling legislation, but the provision ultimately fell out after pushback from the Biden administration.

During the first Trump administration, some states received federal permission to impose work requirements but were stymied by legal challenges. Only Georgia has implemented the program, after prevailing in a challenge from the Biden administration.