By now, it’s become conventional wisdom about Congress: “Moderates always cave.” The more extreme elements sometimes force leadership’s hand, but those near the political center have a tendency to lose their nerve.

Things have apparently gotten so bad for House Speaker Mike Johnson – and the GOP’s political position against continuing key Obamacare subsidies is apparently so perilous – that even that moderates are mutinying.

Wednesday brought one of the most astounding affronts to date to the Louisiana Republican’s increasingly embattled speakership, as moderates joined with Democrats to force a vote to extend soon-to-expire enhanced Obamacare subsidies.

Frustrated over the lack of a deal to vote on an extension and negotiations over features that would make the overall legislation more palatable to the GOP, four more-moderate House Republicans reached for what some of them acknowledged was a nuclear option: They crossed over to support a vote on the clean, three-year extension of the subsidies that Democrats want.

The four Republicans – Reps. Brian Fitzpatrick, Rob Bresnahan and Ryan Mackenzie, all of Pennsylvania, and Rep. Mike Lawler of New York – all signed a so-called discharge petition in quick succession. The petition, which requires 218 signatures to have an effect, effectively bypasses Johnson and requires a vote, whether he likes it or not.

This is remarkable for a number of reasons:

It’s moderates who forced the issue this time.

It’s now the sixth discharge petition to succeed in the last two years. To find the last six successful discharge petitions before that, you’d have to go back decades. (The reason: Discharge petitions are viewed as a direct challenge to leadership, not to be used lightly, because they take away the speaker’s ability to control what gets voted on.)

The petition they signed wasn’t just one the speaker opposed, like with the Jeffrey Epstein files. It was one put forward by the leader of House Democrats, Rep. Hakeem Jeffries of New York. There were other discharge petitions on the table that were more in line with what these Republicans wanted, but Democrats declined to embrace them and made clear this was centrist GOP members’ only option if they wanted a vote.

These GOP members crossed over to buck leadership on, of all issues, Obamacare – the very same federal health care law the party spent years decrying as an abomination that had to be repealed.

This doesn’t mean the Covid-era Obamacare subsidies are now going to be extended. The measure, once passed in the House, would still need to pass in the Senate, where basically the same proposal got a vote last week and fell well shy of the 60 votes it needed (despite getting four GOP votes). It would also need President Donald Trump to sign it, which seems quite unlikely.

But the situation in the House could increase pressure on Republicans to come to the table on extending the enhanced premium subsidies in one form or another.

And it also reinforces and ratchets up the monumental political dilemma Republicans – and Johnson – face right now.

The outcome Wednesday suggests that a number of Republicans think failing to extend the subsidies, in one form or another, simply isn’t an option.

And they have good reason to feel that way, as I wrote last month.

After all, 22 million Americans get these subsidies, and many of them could soon see their premiums double. Seven in 10 Americans favor extending the subsidies, including around half of Republicans in some polls.

And it’s difficult to imagine a worse development right now, at a time when affordability appears to be Trump’s and the GOP’s Achilles heel, than to see millions of people’s health insurance premiums skyrocket, with Republicans being the clear culprits.

(Say what you will about Democrats giving up on their shutdown strategy last month; they at least cast a spotlight on who would be responsible for these subsidies expiring.)

Trump’s numbers on health care are worse than they’ve ever been. In fact, it was his worst issue in a recent AP-NORC poll, with Americans disapproving of his handling of it 69%-29%.

And new polling on Wednesday epitomized how big an issue this could be moving forward and possibly in the 2026 midterm elections. An NPR-PBS News-Marist College poll showed a majority of Americans (54%) were concerned they wouldn’t be able to pay for necessary medical care in the next 12 months. That’s risen significantly in recent years, compared to Gallup polling asking the same question.

As CNN’s David Goldman wrote this month, there are few things as dicey in politics as taking away a benefit that people have become accustomed to. Yet that’s what Republicans are staring down the barrel of – at a really inauspicious time.

Johnson’s posture seems to be that Republicans can put forward their own health care proposal that doesn’t extend these subsidies and, when it doesn’t become law, claim that they at least tried to do something.

But that’s clearly not good enough for members who fear for their constituents’ finances and for their own reelection campaigns.

And on Wednesday, those members made a statement – by doing something very un-moderate.