Del. S. Chris Jones (R-Suffolk), chairman of the House Appropriations Committee, smiles just before the Virginia budget passed Wednesday with Medicaid expansion as a provision. Jones was among the Republican lawmakers who joined Democrats to expand Medicaid. (Bob Brown/AP)

In becoming the first state in nearly two years to open Medicaid to more of its poor residents, Virginia lawmakers found political buffering and momentum in a recent conservative health policy shift in Washington.

Three of four Republican state senators who defected from their caucus’s long-held opposition to expanding Medicaid cited the fact that the Trump administration is allowing states to impose work requirements for the first time in the half-century history of this central piece of the nation’s social safety net.

“We’re going to make sure they’re working, and they’re not going to get a free ride,” one of the four, Sen. Frank W. Wagner (R-Virginia Beach) said in an interview Thursday. “[T]here are people out there who need help, but . . . who could be working and choose not to. . . . I shouldn’t ask other people out there to pay for their lifestyle.”

And Virginia House Speaker M. Kirkland Cox (R-Colonial Heights) characterized his surprise endorsement of the expansion as a way to “reform” the program. Immediately after the Virginia General Assembly adopted the legislation Wednesday, Cox said it “includes what I consider the most conservative set of reforms to Medicaid in the nation as part of a plan to expand healthcare coverage to working Virginians.

“Our plan gives hard-working people a path to self sufficiency through a robust work requirement,” Cox continued, employing the same lexicon used by the Trump administration’s top health officials.

Under the bill, expected to be signed into law next week by Gov. Ralph Northam (D), Virginia’s Department of Medical Assistance must apply within 150 days for federal permission to join a growing number of states that are compelling able-bodied adults to work, prepare for a job or volunteer to qualify for Medicaid.

The expansion, projected to be available to 400,000 low-income Virginians, will begin Jan. 1, whether or not federal officials have approved the work requirement.

Virginia also is borrowing another conservative Medi­caid tool, which was first adopted in Indiana. That state requires everyone in its program — including those living below the federal poverty level — to pay at least small monthly premiums. Virginia has not yet set its income threshhold for charging premiums.

When the expansion takes effect in January, Virginia will go from having especially restrictive Medicaid eligibility rules to allowing residents with incomes up to 138 percent of the federal poverty line to join the program. Federal money will cover at least 90 percent of the cost of insuring people in the expansion group, and the state will tax hospitals to pay for the rest.

Virginia will join 32 states plus the District of Columbia that have expanded Medicaid on a checkerboard around the country that has been filling in during the past four years.

When the Affordable Care Act was passed by a Democratic Congress in 2010, its premise was that the law would broaden access to insurance in two ways — about half through private health plans for people who cannot get affordable coverage through a job and the rest by expanding Medicaid. The bill’s authors did not anticipate a 2012 Supreme Court ruling that gave each state the latitude to expand Medicaid or not.

When the ACA’s Medicaid expansion began at the start of 2014, 25 states plus the District made the change. Three more states trickled in by the end of that year. Pennsylvania and Alaska expanded in 2015. Montana expanded early in 2016, and Louisiana became the last state to do so that July.

Maine voters in November said yes to a ballot initiative approving an expansion, but Gov. Paul R. LePage (R) has refused to implement it, and its fate is now tied up in lawsuits.

Even as Congress’s Republican majority and the Trump administration oppose the ACA’s broadening of Medicaid — and have been working to dismantle significant aspects of the law — grassroots efforts to expand the program continue to percolate in a few states with GOP governors. A ballot initiative is scheduled for November in Utah, and attempts are underway in Idaho and Nebraska to put such initiatives on the ballot.

This big initial wave of Medicaid expansions, followed by a slow, piecemeal embrace is an echo of what happened when Medicaid was created in 1965 as part of Lyndon Johnson’s War on Poverty. Each state had to decide whether to participate, and Virginia was the 42nd, joining the program in mid-1969, more than three years after the first wave of states.

Since Seema Verma, administrator of the federal Centers for Medicare and Medicaid Services, announced in January that the government was opening the doors to states that wanted to create “individual responsibility” requirements within Medicaid, four states have won permission. The first was Kentucky, and the most recent was New Hampshire.

Eight more states have pending applications, and about the same number are at earlier stages of exploring the idea. Like most states so far, Virginia would exempt anyone who is pregnant, over 65 or medically frail. Other beneficiaries would be required to devote 20 hours per month at first — and eventually 80 hours per month — to working, job training, school or other “community engagement” and would be removed from the program if they fail to comply for three months in a year.