Written By Brian Beutler

A few weeks ago, Senate Republicans put together 51 votes for a bill that pays for a huge tax cut for corporations and wealthy heirs with tax increases on working people, a substantial reduction in federal health care spending on the poor and middle class, and $1.5 trillion in additional deficits. One Republican, Tennessee’s Bob Corker, voted against it.

As a matter of crude arithmetic, they could have lost one more vote and still managed to pass the thing, with Vice President Mike Pence on hand to break the tie.

But that arithmetic really was crude, and now that Republicans actually have lost a vote in the Senate, math may not be able to save the GOP’s precious tax cuts. The fate of their bill now turns at least as heavily on the question of whether Republicans in the Senate are as shameless as their fiercest critics in the Trump era insist they are, or whether they’ve reached a breaking point.

On Tuesday night, Democrat Doug Jones defeated Republican Roy Moore in the Alabama Senate special election. When he is seated later this month, the Republican majority will dwindle from 52 to 51.

Again, in theory, Republicans don’t need that vote. If the same members who voted for the last version of the corporate tax cut bill vote for the final language, it will pass anyhow.

But Republican leaders are on the brink of losing more than just the Alabama Senate seat. They are, among other things, also poised to break the promises they made to Sen. Susan Collins (R-ME) to secure her vote for the corporate tax cut bill. If she or any other Republican defects now, the Alabama senators’ vote will become the decisive vote.

To that end, Senate Majority Leader Mitch McConnell is signaling his intent to rush a vote on a final corporate tax cut bill before Jones can be seated.

From McConnell spokesman @StewSays: “Once the state certifies and sends us the paperwork, the new Senator is sworn in. But since the state said they don’t expect to certify until the end of the month, and we expect to finish before the end of the month…” https://t.co/EpkAd41bS0 — Sean Sullivan (@WaPoSean) December 12, 2017

McConnell is a serial violator of American political norms. His procedural extremism surprises no one. But it’s worth noting, as I did last week, that the norm he’s about to destroy is one he personally fought to uphold just eight years ago.

In January 2010, Democrats were one final roll call vote away from enacting health care reform when Republicans unexpectedly won a special Senate election in Massachusetts. McConnell, who was then the Senate Minority Leader, took great umbrage at the idea that Democrats would let a lame-duck interim senator cast the deciding vote on historic legislation. Once the results of the special election were in, though, Sen. Jim Webb (D-VA) headed off the confrontation by pledging not to vote for any health care legislation until Sen. Scott Brown (R-MA) had been sworn in.

As of this writing, no Republicans—even ones, like Sen. John McCain (R-AZ), who has claimed to prize regular order, and Sen. Jeff Flake (R-AZ) who endorsed Doug Jones—have taken a similar stand.

McConnell is a uniquely shameless political tactician. He sat on a Supreme Court vacancy for a full year, claiming disingenuously to be a high minded tribune for the will of the voter, only to gleefully let 2016’s popular vote loser, Donald Trump, seat a right wing justice within weeks of taking office. Now he wants to race unpopular, multi-trillion dollar legislation through the Senate fast enough to outpace the will of Alabama voters. He probably can not be shamed in to withholding votes on the tax bill until Jones arrives in Washington. But he will have no reason to think twice if nobody—starting with Democrats—makes him and his members answer for the seemliness and hypocrisy of the plan they’re putting together.