Republicans’ efforts to gut Obamacare may have backfired on them in Pennsylvania, where Democrat Conor Lamb is hanging on to a thin lead in the special election for a U.S. House seat.

See:Pennsylvania House race still too close to call.

One apparent factor for Lamb’s performance in the district that President Donald Trump carried by 20 points in 2016 was the former marine’s call to make the 2010 law better, not repeal it. That’s what Lamb’s GOP opponent Rick Saccone wants.

But throwing out the law isn’t what the western Pennsylvania district’s voters want, according to a survey released Wednesday by Public Policy Polling. Overall, 44% of voters said they supported Obamacare — formally known as the Affordable Care Act — while 42% oppose it. And voters disapproved of the GOP efforts to repeal Obamacare by 14 points.

Numbers like that have translated into a boost for Lamb, according to PPP. Voters said Lamb better reflected their views on health care by seven points (45% to 38%) over Saccone.

On his campaign website, Lamb says Obamacare “has flaws,” but he hails it for providing coverage to previously uninsured Pennsylvanians. “Our representatives in Congress should be working together to build on that progress, fix what isn’t working, and make the law better,” Lamb says. Saccone supports repeal. The tax law enacted by Trump late last year throws out the individual mandate to have insurance, but keeps Obamacare largely intact overall.

Also see:Republican tax cut message abandoned in Pennsylvania special election.

Political pundits say the race is a referendum on Trump and offers signs for how the midterm elections will go.

There’s at least one more sign that running against Obamacare may be the wrong strategy. A Kaiser Health Tracking Poll released March 1 found 54% of the public said they have a favorable view of the law — the highest level of favorability in Kaiser polls since 2010.

Lamb has declared victory over Saccone, but the race has not been officially called.