The battle over President Donald Trump's Supreme Court nominee Neil Gorsuch has pushed one of Washington's most notorious phrases back into the spotlight: The so-called "nuclear option."
Gorsuch will almost certainly be confirmed one way or another, it's just a question of how.
With Senate Minority Leader Chuck Schumer urging Democratic senators Thursday to stand united and filibuster Gorsuch, Republicans may need to rely on the parliamentary maneuver to kill the filibuster and push Trump's high court pick over the finish line.
The filibuster, which traces its roots to Aaron Burr and the early days of the Senate, has survived an assassination attempt by Henry Clay in 1840s, a 24-hour last-stand against the Civil Rights Act in the 1960s, and the evolution from a long speech to a simple procedure move. Will it die with the Trump presidency, or will Republicans scrounge up enough Democratic defectors to break the filibuster and let the practice live on?
Here's what you need to know.
Will Democrats filibuster?
Yes, but they may not have enough votes to sustain it.
It only takes one senator to start a filibuster, but it takes at least 40 to keep one going in the face of opposition. Schumer is one of several Democratic senators vowing to filibuster. The question is whether 40 of them will stick it out. If eight Democrats join the 52 Republicans, they can achieve the 60-vote bloc necessary to stop a filibuster.
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A filibuster is just a procedural move that blocks the Senate from taking the actual vote on a nominee or piece of legislation. It only takes 50 votes to confirm a nominee (since Vice President Mike Pence can cast a tie breaker), but it can take 60 to get to a vote in the first place.
Will Republicans break the filibuster?
Republicans need eight Democratic votes to break the filibuster, and their first stop is the 10 Democratic senators up for re-election next year in states Trump won, like West Virginia's Sen. Joe Manchin.
A conservative group supporting Gorsuch, the Judicial Crisis Network, has spent millions of dollars on ads targeting Sens. Claire McCaskill in Missouri (where Trump won by 19 points), Joe Donnelly in Indiana (where Trump won by 19), Heidi Heitkamp in North Dakota (where Trump won by 36 points), and Jon Tester in Montana (where Trump won by 21 points).
The group has also targeted Colorado Sen. Michael Bennet, who is not facing reelection, but who hails from Gorsuch's home state. Many Colorado leaders on both sides of the aisle — including the former Democratic governor who first appointed Bennet to the Senate — support Trump's Supreme Court nominee, and Bennet has so far been mum about how he plans to vote.
Republicans are also eyeing other moderates, like Virginia's Mark Warner or Maine's Angus King, an independent who caucuses with Democrats. Meanwhile, others, like Delaware Sen. Chris Coons, have expressed principled objections to filibustering qualified Supreme Court nominees for political reasons.
The challenge for Democrats is that their base has demanded all-out obstruction to Gorsuch, not only because they view him as extreme, but because they say Republicans essentially stole the seat in the first place by refusing to take a vote on former President Barack Obama's nominee Merrick Garland last year.
If Republicans can't sway eight senators, they need to take a more radical step — the nuclear option.
What is the nuclear option?
Republicans could vote in favor of the parliamentary maneuver that would allow the Senate to advance Gorsuch with a simple majority. Members on both sides of the aisle have threatened to invoke the nuclear option throughout the upper chamber's long history, but it wasn't until 2013 that the threats turned into action.
Then-Senate Majority Leader Harry Reid, frustrated by GOP efforts to block Obama's appointees, invoked the nuclear option for nominees to the executive branch and lower federal courts. However, the move did not apply to Supreme Court nominees or legislation.
Some Republicans have been eager to turn the tables and hang the threat over Democrats' heads of extending the nuclear option to Gorsuch.
Could there be a deal?
Other senators from both parties are wary of upending one of the Senate's most powerful tools.
Rumors have swirled on Capitol Hill about a potential deal between a small group of senators to avert the crisis. Democrats would give Republicans enough votes to break a filibuster on Gorsuch, in exchange for a promise that the GOP would not use the "nuclear option" on the next Supreme Court nominee.
The basic architecture of such a deal is intriguing because it would not require buy-in from either party's leadership. It would only take three Republicans to block a rule change in the future, and eight Democrats to give the GOP cloture now, so a small "gang" of lawmakers could act on their own.
Liberals are extremely worried about such a deal. More than 20 progressive groups sent a letter to Democratic senators Thursday warning, "Anything less than a full commitment to resistance, including a filibuster of Judge Gorsuch, would be a betrayal of the communities you represent."
What's at stake?
Invoking the nuclear option would lower the bar for what it takes for a Supreme Court nominee to be confirmed. It would set a precedent that essentially takes an important parliamentary move off the table for the minority party — the filibuster. And the lower threshold could give presidents less of an incentive to nominate judges with views considered mainstream.
Democrats anticipating the change have cited the past three Supreme Court nominees to have confirmation hearings as the standard Gorsuch should be held to.
"If this nominee cannot earn 60 votes — a bar met by each of Obama's nominees, and George Bush's last two nominees — the answer isn't to change the rules. It's to change the nominee," Schumer said on the Senate floor.
The last time the minority party tried to block a Supreme Court nominee was in 2006 during Samuel Alito's nomination. However, the high chamber easily invoked cloture by a 72 to 25 vote, and Alito was confirmed with 58 votes.
Republicans in favor of the move argue that Reid already opened Pandora's box in 2013.
A Politifact analysis found that Senate experts agree going nuclear on a Supreme Court nominee is significant, though not earth-shattering. It essentially widens the scope of what Reid did more than three years ago.
The bigger issue, though, will be if it encourages Sen. Majority Leader Mitch McConnell or future Senate leaders to use the nuclear option on legislation. Lowering the 60-vote threshold on new laws and spending bills could prove even more contentious than using it on nominees.