If Rep. Kevin McCarthy didn’t have a lucky number before, it’s surely 15 now. Just after midnight on Saturday morning, the House of Representatives finally voted to make McCarthy speaker of the House on the 15th ballot — the resolution of an historic, multi-day staredown with conservative hardliners who will now wield tremendous power in the House.

For a while there, McCarthy looked like he might never gain the speaker’s gavel at all. At the height of opposition to him — between the third and 11th ballots — 20 Republicans voted for a non-McCarthy candidate, putting him far away from the majority of votes necessary to win. As I wrote on Wednesday, those dissenters were among the most conservative, most anti-establishment Republicans in the House. The chart below uses incumbents’ DW-NOMINATE scores (ideology scores based on their congressional voting records) to plot them along two axes: left vs. right and pro-establishment vs. anti-establishment.¹ Notice how McCarthy’s opponents are all in the lower-right part of the chart. It’s almost like they are their own political party (more on that in a bit).

On Thursday night and Friday morning, though, McCarthy struck a deal with many of his detractors, and 13 of those who had previously voted for a non-McCarthy candidate came over to his side on the 12th ballot on Friday afternoon.² From there, McCarthy chipped away at his remaining opposition throughout Friday, eventually coming just one vote shy on the dramatic 14th ballot, when Rep. Matt Gaetz stubbornly withheld his vote even after a heated confrontation.

On the following ballot, all of McCarthy’s remaining opponents caved, though not all the way: They voted “present,” essentially an abstention that lowered the threshold McCarthy needed to win. In the end, he received just 216 votes, but that was a majority of the 428 ballots cast for candidates. Thus ended the fifth-longest speaker election in U.S. history by number of ballots, the fourth-longest by number of days, and the longest no matter how you slice it since before the Civil War.

But about that deal. In order to achieve his decade-long ambition, McCarthy made several concessions that will weaken the speakership and strengthen his right-wing, anti-establishment antagonists. One point of contention had been the number of representatives it would take to trigger a “motion to vacate the chair” — essentially, a no-confidence vote in the speaker. Previously, it would have taken a majority of the Republican caucus to call that vote, but McCarthy has reportedly agreed to lower that threshold to just one member.

That sounds like a big change, but it’s really a reversion to how things used to be. Historically, one member has been the normal threshold to trigger a motion to vacate — it was that way until 2019, when Democrats raised it. And in all those years, the only time the motion actually led to a vote was in 1910, although an unsuccessful motion was also filed in 2015. Although the motion might get more use in today’s contentious Congress, it would still require a majority vote of the whole House to actually oust the speaker — meaning five Republicans would have to agree with all 213 Democrats³ for McCarthy to lose his job.

A more meaningful concession is McCarthy’s reported agreement to reserve three seats for hard-core conservatives on the House Rules Committee. The Rules Committee is one of the most powerful committees in the House — setting the rules (duh) of debates, choosing which pieces of legislation to bring up to a vote and even rewriting legislation that has already passed another committee. If the Rules Committee maintains its traditional partisan composition — nine members of the majority party, four of the minority — then it could have six McCarthy-aligned Republicans, three insurgent Republicans and four Democrats, which means that McCarthy-aligned Republicans would constitute a minority on the committee. In the words of one conservative activist, that would effectively make the Rules Committee a “European-style coalition government” where the hard-right bloc is like a third party, and McCarthy and his allies would have to negotiate with them (or Democrats) to get anything done.

This, in turn, could make it more likely that the federal government shuts down and/or defaults on its debt in 2023. The insurgent wing of the GOP was at the center of the government shutdown fight in 2013 and the debt ceiling fight in 2011, and McCarthy has agreed to fight for their preferred spending cuts here in 2023. But of course, nothing can become law without buy-in from the Democrats who still control the Senate and the White House, who are about as ideologically far removed from the conservative hardliners as it gets. So this week’s fight in Congress could presage other, even higher-stakes ones — and now, Kevin McCarthy is the lucky duck who gets to be in the middle of them.