With one hasty and excruciatingly narrow vote, House Republicans have all but guaranteed that health care will be one of the most pivotal issues shaping the next two election cycles — including congressional, gubernatorial and state legislative races in the 2018 midterms and President Trump’s likely reelection bid in 2020.

Just as Democrats were forced to defend Obamacare in the 2010 midterms — the result was a coast-to-coast drubbing that President Barack Obama called a “shellacking” — Republicans this time will be in the hot seat.

GOP members of Congress will be asked to defend their votes for a bill that could strip insurance from 24 million Americans and jack up premiums and deductibles for the country’s sickest and oldest citizens.

Governors, gubernatorial candidates and state legislators, meanwhile, will be asked whether they intend to “opt out” of provisions in the Affordable Care Act that are overwhelmingly popular with voters, as is permitted under the Republican plan. Their plans for state Medicaid programs also will be scrutinized if massive GOP cuts to Medicaid funding are realized.

“Health care will be a defining issue,” said John Del Cecato, a Democratic strategist. “It’s hard to say if it will be the only issue between now and 2018, but I can’t recall a vote this significant in terms of its political potential in 20 years.”

House Speaker Paul D. Ryan (R-Wis.) and 216 of his GOP colleagues voted yes for the American Health Care Act on Thursday. (Melina Mara/The Washington Post)

For example, Tom Perriello (D), whose 2010 vote for the Affordable Care Act helped cost him his seat in the House, is now making his support for Obamacare a centerpiece of his pitch to become governor of Virginia — depicting the Republican health-care plan in his latest ad as an ambulance being crushed at a junk yard.

A picture of Rep. Mimi Walters (R-Calif.) taking a selfie at Trump’s Thursday Rose Garden celebration to cheer House passage of the GOP bill quickly made its way into a fundraising appeal from one of her Democratic challengers, Kia Hamadanchy — with the subject line, “I am appalled.”

And when 217 Republicans cast “aye” votes for the GOP plan on the House floor on Thursday afternoon, their Democratic colleagues bid them a rowdy adieu by singing, “Na na na na, na na na na, hey, hey, hey, goodbye.”

“Health care is a riptide,” said Mark Putnam, a Democratic media strategist. “It has now jumped from being just a federal issue to being a state issue because states are given the right to opt out of protections for preexisting conditions. Legislators and governors will have to answer for that.”

Trump’s political advisers calculated that it was less damaging electorally for congressional Republicans to pass a bill that some of their constituents see as deeply flawed than to have passed nothing at all.

“I think it’s a lot worse to have said for six years, since 2010, that this is something you were going to do and then when you had the chance to do it, you didn’t,” said Marc Short, the White House’s director of legislative affairs and a veteran party strategist.

(Jenny Starrs/The Washington Post)

Short said Thursday’s vote will help endear Republican House members to the conservative base as well as to Trump. “I think those members who stood with the president, the president will remember that and their voters will remember that,” he said.

In remarks at the Rose Garden event, Trump said the current law had been “a catastrophe” and made sweeping assurances about the GOP’s replacement measure, which he said he was confident would pass the Senate despite some strong reservations from Republican senators.

“Yes, premiums will be coming down,” Trump said. “Yes, deductibles will be coming down. But very importantly, it’s a great plan. And ultimately, that’s what it’s all about.”

Health care already has reverberated in some special elections this spring, including in the race for the congressional seat in Georgia that was vacated by Tom Price when he became Trump’s secretary of health and human services.

On Friday, the Cook Political Report, which evaluates the political environment in all 435 congressional districts, shifted its assessments in 20 House races in favor of the Democrats — some from solidly Republican to likely Republican, others from likely Republican to leaning Republican, and more still from leaning Republican to toss-up.

Thursday’s vote “guarantees Democrats will have at least one major on-the-record vote to exploit in the next elections,” wrote David Wasserman, the report’s House editor. He added that the new dynamic “is consistent with past scenarios that have generated a midterm wave” and “almost a mirror image of 2010.”

Polling shows that the public disagrees with Republican health-care plans. Thirty-seven percent of Americans support repealing and replacing the law known as Obamacare, while 61 percent want to keep it and try to improve it, according to a Washington Post-ABC News survey in April.

A Quinnipiac University survey in March found that American voters overwhelmingly disapproved of an earlier version of the House health-care plan by 56 percent to 17 percent.

The latest version of the American Health Care Act was passed in the House on Thursday by a vote of 217 to 213 without an analysis from the Congressional Budget Office, which would determine its cost and impact on insurance coverage.

The bill would shift power to states to set some health insurance rules, slash Medicaid spending by more than $800 billion and cut nearly $600 billion in taxes under the health-care law, most of which will benefit the wealthiest Americans. Obama’s Affordable Care Act also prohibited insurers from charging more to customers with preexisting medical problems — one of its more popular provisions — but the Republican bill would lift that prohibition and give states the option to let insurers charge more for them.

Republican pollster Neil Newhouse, who completed focus groups in Ohio on Thursday evening that briefly touched on this topic, concluded that there was “considerable confusion over what was in the legislation.”

“The GOP would have likely faced a backlash from its base had they not passed repeal/
replace,” he said. “There is a clear sense that both Trump and Republicans had promised as much.”

Newhouse added that the Democrats in his focus groups “seemed to be in a mood to punish those who supported the AHCA” and were “more energized and focused” than the Republicans.

Away from the White House, there was a palpable sense of doom among some GOP campaign operatives, who imagined how easy it would be for Democratic challengers to launch potent attacks about health care. Even many House Republicans who voted for the bill are already distancing themselves from it, arguing that problems would be solved in the Senate.

“What we’ve done here is political malpractice,” said Rick Wilson, a GOP strategist who is sharply critical of Trump. “Democrats will run ads with weeping parents who can’t cover their premiums and Little Johnny dying. . . . Or ‘Congressman Smith voted to end coverage of preexisting conditions. That means 875 people here in X district who have cancer cannot be covered.’”

Wilson added, “Republicans in the House right now should be on their knees praying for the Senate to kill this,” arguing that the line of attack would be less powerful if the bill does not become law.

Jesse Ferguson, a Democratic operative who has advised scores of House candidates, said, “It doesn’t take even a good ad-maker to figure out how to tell the story of the damage that this bill does to people’s health care, whether it’s the AARP saying it charges people over 50 five times more, or the American Cancer Society saying it guts protections for preexisting conditions. There’s no real way to defend that to voters.”

Democratic leaders are trying to seize the political advantage and use the issue of health care to galvanize a liberal base that was demoralized by Trump’s election. They are reporting a surge in new Democratic candidates looking to run in next year’s midterms, even in districts and states considered solidly Republican.

Rep. Nancy Pelosi (D-Calif.), the House minority leader who lost her speakership after the 2010 midterms and has been plotting her return to the majority ever since, declared Thursday that Republican House members had “walked the plank” with their support for the American Health Care Act.

“This vote will be tattooed to them,” Pelosi said. “They will glow in the dark.”

Of course, Democrats also risk being too bullish.

“I love going into a campaign where the opposition is blindly overconfident,” said Chris LaCivita, a Republican strategist. “I think they’re just going to put all their eggs in one basket.”

Ashley Parker contributed to this report.