More than 200,000 Oklahomans will qualify for the state’s Medicaid expansion. That coverage is in jeopardy, however, because of the lawsuit targeting the Affordable Care Act.

In a historic decision, Oklahoma voters on Tuesday bucked Republican Gov. Kevin Stitt and agreed to expand Medicaid health insurance to an estimated 200,000-plus low-income residents.

Voters approved the ballot measure by a narrow 50.5% to 49.5% margin, making Oklahoma the 37th state to expand Medicaid under the Affordable Care Act. 

The passage of State Question 802 is expected to dramatically reduce Oklahoma’s uninsured rate by extending Medicaid health insurance to those earning up to 138% of the federal poverty line, which is about $17,200 for an individual or $35,500 for a family of four. Oklahoma currently has the second-highest uninsured population in the nation, behind Texas.

The Oklahoma Health Care Authority previously projected that about 215,000 residents would qualify for Medicaid expansion. That number is likely to be much higher, however, given the number of Oklahomans who have lost their jobs and employer-sponsored health insurance due to the economic shutdown amid the coronavirus pandemic. One estimate from the Oklahoma Policy Institute found that nearly 100,000 Oklahomans have lost their health insurance during the pandemic, with between 40,000 to 80,000 of them eligible for Medicaid expansion.

By approving the ballot measure, voters also delivered an implicit rebuke of the GOP’s healthcare agenda, which includes trying to repeal the Affordable Care Act in a case set to be heard by the Supreme Court this fall. If the Court sides with Republicans and the Trump administration in striking down the ACA amid a pandemic, it would also invalidate Medicaid expansions across the country, taking away health insurance from more than 12 million adults and roughly 3 million children who receive coverage via Medicaid or the Children’s Health Insurance Program, according to the Urban Institute. 

RELATED: The GOP Wants to Repeal the ACA During a Pandemic. Democrats Are Trying to Expand Coverage.

While the Trump administration focuses on repealing the ACA and Medicaid expansion without a plan in place to replace it, the success of the ballot measure in deeply red Oklahoma—the state went for President Trump by a 36-point margin in 2016—highlights the growing popularity of Medicaid expansion.

Oklahoma is now the fifth Republican-led state to expand the program via ballot measure since 2017, joining Idaho, Maine, Nebraska, and Utah, where voters also worked around obstructionist Republicans to expand coverage.

Those states, however, expanded the program by amending state statutes, while Oklahomans voted to amend the state Constitution in order to expand Medicaid. Amending the Oklahoma Constitution will prevent the Republican-controlled state legislature, which has opposed Medicaid expansion for a decade, from watering down the program or rolling back coverage, as Republican lawmakers have tried to do in Utah and Idaho.

“Before tonight, we were the second to worst state in the country when it came to the number of people going without health care. After tonight, we are the only state in the nation to guarantee access to health care that politicians can never take away,” Amber England, the manager of the campaign in favor of the ballot initiative, said on Tuesday evening.

Amber England
Amber England, campaign manager, Yes on 802, addresses supporters via the internet Tuesday, June 30, 2020, in Oklahoma City, as due to Covid-19 concerns, a virtual watch party replaces the normal watch party, as they await results in a vote in which Oklahoma voters are deciding whether to amend the state Constitution to expand Medicaid health coverage to tens of thousands of low-income residents. (AP Photo/Sue Ogrocki)

Some Republican opposition to Medicaid expansion has eroded in recent years, especially in rural areas where hospitals have suffered financial problems or closed. Kevin Penry, a Republican and retired pastor from Edmond, Oklahoma, said that before going on Medicare last month he had to buy expensive insurance on the federal marketplace, which “really made me feel for folks who are in a difficult financial situation.” He said he voted for the expansion.

Citing uncertainty about future costs for the state, Gov. Stitt maintained opposition to the expansion. “We have a billion-dollar shortfall next year,” Stitt said at a recent forum hosted by Americans for Prosperity, a conservative group that opposed the ballot measure. The state would have to “either raise taxes or to cut services somewhere else like education, first responders, or roads and bridges” to cut additional Medicaid costs, he said.

Stitt had instead proposed his own limited expansion, under which Oklahoma would become the first state to work with the Trump administration to cap Medicaid spending, a long-time goal of Republicans eager to roll back the public insurance program. Research has found that the administration’s “block grant” program would dramatically reduce federal funding for Medicaid, forcing states to make significant cuts to Medicaid benefits—including which prescription drugs are covered—and impose higher out-of-pocket costs on enrollees. 

RELATED: Trump Said He Wouldn’t Cut Medicaid. This New Plan Cuts Medicaid.

By approving the ballot measure on Tuesday, voters have made it nearly impossible for Stitt to go through with his plan as proposed. Oklahoma Health Care Authority spokesperson Katelynn Burns told Modern Healthcare that some aspects of the governor’s plan will be incompatible with the new Medicaid expansion, and the agency is collaborating with the Center for Medicare & Medicaid Services and state leaders to evaluate available options.

The federal government would cover an estimated 87% of the projected annual cost of expansion of about $1.3 billion, according to the Oklahoma Healthcare Authority. The total cost may rise, however, as more Oklahomans enroll in the program, but thanks to the Affordable Care Act, the federal government will still cover the lion’s share of the cost. 

State lawmakers will now have to determine how to cover their portion, as the state faces a coronavirus-induced budget shortfall. To help fund the proposal, the legislature is expected to increase a fee that hospitals pay from 2.5% to 4%, which would generate about $134 million annually. Stitt vetoed such a measure earlier this year.

The initiative requires Oklahoma officials to begin enrolling members no later than July 1, 2021.

The Associated Press contributed to this report.