Millions more Americans signed up for taxpayer-funded health care coverage like Medicaid and the Affordable Care Act’s marketplace during the Biden administration, a shift lauded by Democrats as a success.

But Republicans, who are looking to slash federal spending and offer lucrative tax cuts to corporations and wealthier Americans, now see a big target ripe for trimming. The $880 billion Medicaid program is financed mostly by federal taxpayers, who pick up as much as 80% of the tab in some states. And states, too, have said they’re having trouble financing years of growth and sicker patients who enrolled in Medicaid.

To whittle down the budget, the GOP-controlled Congress is eyeing work requirements for Medicaid. It’s also considering paying a shrunken, fixed rate to states. All told, over the next decade, Republican lawmakers could try to siphon billions of dollars from the nearly-free health care coverage offered to the poorest Americans.