Senate Majority Leader Mitch McConnell and President Donald Trump face a high-stakes Saturday showdown with a handful of key senators that will decide whether the Supreme Court tilts to the right — perhaps for decades to come. But it might fall to Vice President Mike Pence to put him on the highest bench in the land.

After the nomination of Brett Kavanaugh — who has faced multiple sexual assault allegations and criticism for his angry rebuttal that included sharp criticism of Senate Democrats — cleared a procedural hurdle Friday morning, McConnell and Trump needed to secure 50 GOP votes.

All eyes again Saturday will be on GOP Sens. Jeff Flake of Arizona, Susan Collins of Maine and Lisa Murkowski of Alaska, as well as Democratic Sen. Joe Manchin III of West Virginia as he faces a tough reelection bid in a deeply red state. On Friday, Flake and Collins voted with Republicans to limit debate and move to a final vote. Murkowski voted with Democrats, and Manchin with Republicans. The final tally was 51-49.

But things are not that simple. Sometimes, senators vote to limit debate when they feel — even if they oppose a nominee or bill — that it is just time to vote and move on. McConnell and Trump can lose one Republican (likely Murkowski), even if Manchin votes “no.” That would create a 50-50 tie.

Cue Pence, who a White House source says will be in Washington all weekend with his 51st and decisive vote.

Here are some memorable vice presidential votes, including several by Pence. He has provided the final vote nine times already. His most recent predecessor, Joseph R. Biden JR., did not break a tie in eight years.

Adams’ opening acts

The country’s first vice president, John Adams, cast a record 29 tie-breaking votes. The non-partisan Wilson Center notes that VP No. 1, at first at least, frequently joined floor debates. One problem: The center points out Adams angered members by “lecturing Senators like a schoolmarm.” Eventually, he was hit with a threat of a motion to silence him, and he focused on procedural matters.

[Trump to Senators: Ignore ‘Elevator Screamers’]

One was to break a logjam over a measure that would have kept the country’s official capital in New York for two additional years.

Gore’s gun show

Vice President Al Gore in May 1999 cast the decisive vote to pass an amendment from then-Sen. Frank Lautenberg, D-N.J., that would have regulated firearm sales at gun shows.

The amendment was adopted, but the broader bill died in the House.

The (Senate) Decider

President George W. Bush famously described himself as “The Decider.” But on eight occasions, it was up to his vice president to cast the deciding vote on the Senate floor.

[Kavanaugh Nomination Clears Key Hurdle, Final Vote Teed Up]

And perhaps none of those eight were bigger than his 2003 vote in favor of an amendment from Sen. Don Nickles, R-Okla., that nixed dividend taxes for the next three years. “It would encourage investment, it would encourage jobs, it would encourage growth,” Nickles said on the floor just before Cheney broke the tie.

The broader tax cut bill to which the amendment was attached was later signed into law by Bush.

DeVos deadlock

The Senate was evenly divided early in Trump’s tenure over the nomination of Betsy DeVos to become Education secretary.

Pence’s motorcade arrived at the Capitol in dramatic fashion as he, for the first time, cast a decisive vote. As is frequently the case, Collins and Murkowski were front and center that day, too. Both voted against DeVos’ confirmation, saying she was unqualified for the job.

Pence’s vote was historic: It marked the first time a Veep had cast the decisive vote to confirm a Cabinet official.