The US House of Representatives on Thursday passed legislation to re-establish tax credits that lowered premiums for Affordable Care Act (ACA) health plans, after a small group of Republicans broke ranks and joined with Democrats to defy Donald Trump on a key healthcare issue that could sway voters ahead of the November midterm elections.

The chamber voted 230-196 to approve a bill that would extend for three years the credits, which were first created under Joe Biden but expired at the end of last year despite a concerted effort by the Democratic minority to continue them.

All Democrats voted for the measure along with 17 Republicans, many of whom were moderates who said they could not tolerate a hike in healthcare costs for their constituents, but acknowledged the House measure will likely be revised by the Republican-controlled Senate before it is enacted.

“I am voting in favor of this discharge and of this legislation to send it to the Senate, so that the Senate will have the opportunity to put forth a reform package that can pass Congress and become law,” Republican congressman Mike Lawler said during a preliminary vote on the bill on Wednesday.

Trump has opposed extending the tax credits, and the Senate last month rejected a Democratic-backed measure similar to the bill that passed the House. Experts expect that premiums for enrollees of the plans will roughly double without the subsidies.

The Republican speaker, Mike Johnson, has opposed the credits, arguing they would enable fraud while calling the landmark 2010 law passed under Barack Obama the “Unaffordable Care Act”. Democrats made an extension a centerpiece of their demands during the record-long government shutdown that began in October, while moderate Republicans sought to strike a compromise that would be palatable to both parties.

But after Johnson refused to bring any deal to the floor, four Republicans last month signed a discharge petition that forced a vote on the legislation extending the credits for three years, in a significant rebuke of the speaker.

“All of those options were rejected, unfortunately, by House leadership, so it left us with two options – either expiration or clean extension. And clean extension is a far better option, in my view, and that’s why I proceeded down the path that I did,” House representative Brian Fitzpatrick, one of the four Republican signatories, said in an interview with NPR on Thursday.

Fitzpatrick predicted that the Senate will “put their stamp on” the three-year extension, and then the House will consider it again.

Democrats see the tax credits as part of their emphasis on fighting the “affordability crisis”, a key plank of their pitch to voters ahead of the midterm elections in November, when they will seek to retake the Senate and House. Trump, meanwhile, has dismissed the concerns about affordability as a “hoax”, though Johnson has said that Republicans plan to outline their own proposals to lower healthcare costs in the weeks to come.

“The affordability crisis is not a hoax, it is very real, despite what Donald Trump had to say,” the House minority leader, Hakeem Jeffries, said in a Thursday morning press conference. “Today, we have an opportunity to take a meaningful step forward, lower the high cost of living for everyday Americans, particularly as it relates to healthcare.”

His counterpart in the Senate, the minority leader Chuck Schumer, said that the party did not plan to let the issue go.

“Democrats are going to make healthcare and other high costs, the high cost of living, the No 1 issue for all of 2026,” Schumer said.