Protesters rally at the Capitol to oppose the House Republicans’ bill to repeal the Affordable Care Act on May 4. (Oliver Contreras/For The Washington Post)

The health-care bill passed by the House brought Republicans closer to their goal of erasing Obamacare from the books. But it also revived another long-
cherished aspiration: cutting off the flow of federal funds to Planned Parenthood.

A provision in the bill temporarily blocks the 100-year-old nonprofit women’s health organization and abortion provider from participating in the Medicaid program. If enacted, it would deal a devastating blow to an organization that provides reproductive services and other health care to 2.5 million people annually.

It is far from certain that the measure will become law, as it must still pass the Senate, where both the Planned Parenthood provision and the larger bill are likely to encounter stiffer political and procedural obstacles. The American Civil Liberties Union also has threatened legal action to prevent such a law from taking root.

But it represents a significant, initial victory for conservatives who have long sought to undercut the country’s largest abortion provider and who had extracted a promise from President Trump during his campaign that he would sign a bill defunding Planned Parenthood.

The twin achievements led conservatives to call the day historic.

“Today is a day that should and will be remembered,” Tony Perkins, president of the Family Research Council, said in a statement. “The House GOP today fulfilled its nearly decade-old promise to pass a bill that replaces Obamacare with a law that is pro-life and reduces premium costs for the American people.”

Planned Parenthood’s supporters called the defunding effort just one aspect of the broader health-care bill that will harm women, arguing that the new bill also would eliminate the requirement that all individual health plans cover maternity care and would change the way preexisting conditions must be treated.

Although the Republican plan would retain a federal requirement for insurers to cover maternity care and other essential health benefits, it provides a pathway for states to opt out of those requirements by getting a special waiver. States also could free insurers from a prohibition on raising premiums on patients with preexisting conditions, as long as they make a high-risk insurance pool available.

“From gutting maternity coverage to blocking women from getting health care at Planned Parenthood to eliminating guaranteed coverage for those with preexisting conditions, the measure passed today will drive health care out of reach for millions,” said Nancy Northup, president of the Center for Reproductive Rights.

Planned Parenthood and other abortion providers already are banned from billing taxpayer-funded programs for the controversial procedure. But conservatives say abortion providers should not be able to reimburse for Medicaid funds, even for health services such as cancer screenings and birth control, arguing that the money is all fungible.

The vote comes as Planned Parenthood has been filling town hall meetings with pink-clad supporters and participating in rallies in Pennsylvania, Nevada and elsewhere to highlight support for the organization. They continued the protests even as the health-care bill appeared dead for a time, after an initial effort to pass it collapsed in March.

Anxious about the rockier path the bill faces in the Senate, Republicans have included the defunding language in their budget reconciliation bill, seeing it as the likeliest pathway because they can pass it with a simple majority and won’t need buy-in from Democrats in the chamber.

The outcome could have a major impact on Planned Parenthood, which has more than 600 health centers across the country and provides a range of services, including contraceptive prescriptions, cancer screenings, testing for sexually transmitted diseases and abortion services. About 43 percent of its budget — close to $550 million — comes from government grants and reimbursements, with Medicaid representing the vast majority of that money.

Some Planned Parenthood clinics likely would close if the bill becomes law, partly because of the defunding provision but also because the broader bill could result in many Americans losing their eligibility for Medicaid. About ­60 percent of Planned Parenthood’s patients rely on federal public health programs.

But Planned Parenthood officials say the true victims are the patients who will be forced to find another health-care provider that accepts Medicaid, pay out of pocket, or simply go without care.

Heads of different affiliates have been gaming out what might happen to patients if clinics have to close. They also have stepped up fundraising. Adrienne Mansanares, chief experience officer for Planned Parenthood of the Rocky Mountains, said the organization is contacting donors to enlarge its “critical need fund,” which subsidizes care for uninsured people who pay for medical treatment out of pocket.

“To block Planned Parenthood is clearly a political move to single out one nonprofit business and to say anyone who is using their insurance to go to their trusted medical provider there, you can no longer use your insurance,” she said.

Planned Parenthood’s critics contend that such warnings are scare tactics, noting that the bill would redirect the millions of dollars Planned Parenthood gets annually through Medicaid to other health centers that they say could absorb the patients. Besides, they say, the government should not be in the business of supporting an organization that was responsible for more than 300,000 abortions during the 2014-2015 fiscal year.

The health-care bill “will do what is right by stopping taxpayer funding for abortions and refocusing Medicaid on those who most need it,” said House Majority Whip Kevin McCarthy (R-Calif.).