Tuesday afternoon, Senate Majority Leader Mitch McConnell, R-Ky., began the process to change chamber rules to shorten debate time for lower court judges and sub-Cabinet executive nominees. And he did so by voting against a resolution that would have done that.

Let’s back up. For a while, there’s been talk of invoking the Senate’s “nuclear option” to create an express lane in the Senate confirmation process by lowering the minimum procedural debate time on some nominees from 30 hours to two.

A resolution that would have done that failed to clear the necessary 60-vote threshold to invoke cloture by a vote of 51-48. But that’s just the beginning of how the process works.

The “nuclear option” is just a much cooler term for the parliamentary procedure by which the Senate can change its rules with a simple majority instead of the standards two-thirds vote.

McConnell needed a failed vote to trigger the process by which the chamber can change the rules on confirmations with fewer than 60 votes. He voted against the measure so that he’d be able to bring it up for reconsideration later, which is key to the process. Under Senate rules, members can only bring up a bill for reconsideration if they were on the prevailing side of the original vote, so if a senator wants to reconsider something later, he can switch his vote when he sees that it’s going to fall short of 60 votes to invoke cloture.

Once the bill is up for reconsideration, the majority leader can raise a point of order about how the rules are applied. His point of order can then be rejected by the chair. But the key here is that only a majority of the chamber is needed to overturn a ruling of the chair and change precedent.

The Congressional Research Service has a couple of handy breakdowns about how this process worked in 2013 when then-Majority Leader Harry Reid, D-Nev., invoked it to change the vote threshold for executive branch and lower court nominations and in 2017 when Senate Republicans changed the rules for Supreme Court nominations for Justice Neil Gorsuch.

At a Tuesday press conference, McConnell said the Senate would be dealing with the issue “through the balance of the week.”