Nine House Republicans bucked their party leaders on Wednesday evening to advance a vote on a Democrat-led healthcare bill.

The nine GOP lawmakers’ support was key to pushing ahead on a vote to extend enhanced Obamacare subsidies that expired at the end of last year. A vote on the bill itself is now expected Thursday afternoon.

It’s a blow to Speaker Mike Johnson, R-La., who argued for weeks that the majority of House Republicans were opposed to extending the COVID-19 pandemic-era tax subsidies.

But a significant number of GOP moderates were frustrated that their party leaders in the House and Senate had done little to avert a price hike for millions of Americans’ insurance premiums.

Four of them signed onto a discharge petition filed by House Minority Leader Hakeem Jeffries, D-N.Y., last month aimed at forcing a vote on extending the subsidies for three years over House GOP leaders’ objections.

A discharge petition is a mechanism for getting legislation considered on the House floor even if the majority’s leadership is opposed to it.

Those four lawmakers — Reps. Mike Lawler, R-N.Y., Brian Fitzpatrick, R-Pa., Rob Bresnahan, R-Pa., and Ryan Mackenzie, R-Pa. — were among the nine to vote for advancing Jeffries’ petition on Wednesday.

At the time, they criticized leadership in both parties for not working toward a bipartisan solution earlier and said they were left with little choice in the matter.

The other five lawmakers who voted to advance the petition were Reps. Nick LaLota, R-N.Y., Maria Salazar, R-Fla., David Valadao, R-Calif., Max Miller, R-Ohio, and Tom Kean Jr., R-N.J.

The bill is expected to pass the House on Thursday, but it is all but certain to die in the GOP-controlled Senate.

Similar legislation led by Senate Democrats failed to reach the necessary 60-vote threshold to advance in December.

The vast majority of Republicans believe that the subsidies are a COVID-era relic of a long-broken federal healthcare system. Conservatives argued that the relatively small percentage of Americans who rely on Obamacare meant that an extension would do little to ease rising health costs that people across the country are experiencing.

But a core group of moderates has been arguing that a failure to extend a reformed version of them would force millions of Americans to grapple with skyrocketing healthcare costs this year.

House Republicans passed a healthcare bill in mid-December aimed at lowering those costs for a broader swath of Americans, but that legislation has not been taken up in the Senate.