Less than an hour after an appeals court invalidated part of the Affordable Care Act and pushed off a decision on the rest of it, congressional Democrats began punching, accusing President Trump and his party of imperiling Americans’ insurance and consumer health protections.

But on a debate stage Thursday night, Democrats vying for their party’s nomination for president did not mention the major court decision. Instead of pivoting to defend the law and branding Republicans as existential threats to the ACA — a strategy that helped Democrats win control of the House last year — the candidates continued their months-long disagreement over whether a single-payer health-care system would be best for the country.

For Republicans, that split-screen Democratic treatment represents both danger and opportunity heading into the 2020 elections. The 98 pages of dusty legal prose redefines battle lines the parties have drawn on health care — an issue on voters’ minds more than nearly any other. But the ruling spares the GOP the political chaos that would have erupted if the New Orleans-based federal court had given the president and other Republicans what they have long sought — elimination of the entire law.

“The court provided Republicans the opportunity” to continue talking about smaller-bore changes that please consumers, such as drug prices, “without having to jump into a health-care debate that is extremely unpredictable,” said Josh Holmes, a Republican consultant and former chief of staff to Senate Majority Leader Mitch McConnell (R-Ky.).

When it comes to health care and elections, politicians tend to succeed when they can claim the high ground as protectors of aspects of the health-care system that voters value, according to candidates and strategists in both parties.

“The dominant fact about the politics of health care in the United States is that most people are afraid of sweeping changes to their health-care arrangements, imposed by Washington,” said Ramesh Ponnuru, a conservative scholar affiliated with the American Enterprise Institute.

Through that lens, this week’s ruling, by a three-judge panel of the U.S. Court of Appeals for the 5th Circuit, is a gift to Democrats who take it, strategists said. The lawsuit was started by a coalition of Republican attorneys general, and the Trump Justice Department took their side, at first arguing that only the insurance requirement was unconstitutional and later joining the attorneys general’s stance that the whole law was invalid.

The two Republican-appointed jurists in the panel’s majority directed a conservative Texas trial judge, who ruled a year ago that the entire ACA was unconstitutional, to “employ a finer-tooth comb” and reconsider whether the rest of the statute may remain after they ruled against the requirement that most Americans carry insurance.

As a result, parts of the law in limbo include its popular insurance protections for the millions of Americans with preexisting medical conditions, an expansion of Medicaid in three dozen states, federal subsidies for most people who buy health plans through marketplaces created under the law, more preventive care for older Americans and more.

“It leaves the Democrats in a great position, because it elevates the possibility and concern that the ACA could disappear,” said Celinda Lake, a Democratic pollster who has focused on health care as an election issue and is working for former vice president Joe Biden’s campaign. “It also removes a limited amount of credibility Trump was acquiring based on his rhetoric around prescription drugs. This shows he continues to be relentlessly focused on getting rid of the ACA.”

Democratic congressional candidates are eager to redeploy their strategy from the 2018 midterm elections in which they gained the House majority by portraying themselves as the law’s guardians.

“Here’s what this means: This lawsuit still threatens to raise health care costs and eliminate protections for Arizonans with preexisting conditions,” said Mark Kelly, a top Democratic Senate recruit challenging Sen. Martha McSally (R-Ariz.).

In strikingly similar language, Jaime Harrison, challenging Sen. Lindsey O. Graham (R-S.C.), accused his opponent of “trying to put the health of the millions of Americans that rely on the ACA at risk.”

The ruling “is unifying for the Democrats,” Ponnuru said. In the presidential primary race, the candidates “are obviously deeply divided about their own health care plans. The voters are divided. . . . They are all united about this lawsuit.”

But in not striking down the entire ACA, the appellate ruling carves out space for Republicans to tell voters that nothing is changing for now. In practical terms, holding that the insurance mandate on individuals is unconstitutional has little immediate effect, coming two years after a Republican Congress voted to eliminate the financial penalty the law had imposed on people who failed to have insurance.

Since Wednesday’s ruling, Republicans have been relatively quiet. Most who have spoken publicly have emphasized that no American’s insurance is changing at the moment.

In stopping short of voiding a law of more than 2,000 pages, the Fifth Circuit spared Senate Republicans and Trump — who has promised a replacement plan but not produced one — of the responsibility of drafting new consumer protections they say they would preserve.

“It helps when you can think through the potential problem, rather than trying to legislate with a gun to you head,” Holmes said.

Asked Thursday about the political impact of the court opinion, Kayleigh McEnany, the Trump campaign’s national press secretary, did not answer directly. “President Trump has lowered prescription drug costs, expanded health care choice, protected preexisting conditions, and removed the vastly unpopular and unconstitutional individual mandate,” she said in a statement. “The American people recognize that President Trump’s policies are working as Democrats threaten to deprive millions of Americans of their employer-provided health care.”

That reference to Medicare-for-all plans, championed by Sens. Bernie Sanders (I-Vt.) and Elizabeth Warren (D-Mass.), is what makes the health-care issue “a double-edged sword in 2020,” said Republican pollster Chris Wilson.

“On the one hand, preexisting conditions were a winning issue for Democrats in 2018 and one many Republicans didn’t answer as well as they should have,” he said. “On the other hand, the big difference between 2018 and 2020 is that Medicare-for-all and government takeover of health care has moved from a fringe position. . . . So now Republicans have a way to hit back.”

It enables Republicans, hoping to ward off Democratic attacks, to counter with claims that Democrats are the ones working to unravel the current health care system.

“The court not ruling on the constitutionality of Obamacare leaves all of this in play through next November,” Wilson said in an email.

Legal scholars said the limbo period probably will last well past the November elections, as Judge Reed O’Connor, of the U.S. District Court of the Northern District of Texas, reconsiders whether the rest of the ACA can be considered legally distinct from the insurance requirement, the Fifth Circuit reviews that ruling and the case almost certainly then goes to the Supreme Court.

The Democratic attorney general leading the fight to preserve the law hopes to shorten that limbo.

“It’s time to stop this uncertainty,” California Attorney General Xavier Becerra said Thursday, contending the Fifth Circuit panel “set a time bomb by sending it back to a lower court.”

Becerra told reporters that while he needs to confer with his 20 Democratic counterparts, he wants to ask the Supreme Court to take the case in time to hear and decide it by late spring. He acknowledged the high court already has decided on most of its cases for this term but contended it is not too late.

Amid the swirling politics, some questioned whether the timing of the Fifth Circuit’s opinion had a political element, since it was published during the House floor debate just before the chamber’s vote to impeach Trump.

“It’s always hard to know,” said Nicholas Bagley, a pro-ACA University of Michigan law professor who said the opinion “has the fingerprints of a partisan hit job.” He said the Fifth Circuit panel could have been trying to finish its work before Christmas, or the two Republican-appointed judges in the majority could have been struggling over the opinion’s legal reasoning or the Democratic-appointed judge could have been slow in writing her dissent.

Still, Bagley said, “you release a highly partisan opinion on a day the country is distracted, it’s reasonable to ask whether the timing was deliberate.”