Updated

Senate Republicans and Democrats on Wednesday will continue a floor debate on President Trump’s Supreme Court pick to replace the conservative Antonin Scalia.

Sen. Jeff Merkley, D-Ore., took the floor of the Senate on Tuesday night and started a marathon session to protest the Republican blockade of President Obama’s nominee for the seat, Merrick Garland.

"Make no mistake: this is a stolen seat — & if this theft is completed, it will undermine the integrity of the court for decades," Merkley tweeted as he began.

Merkley's speech wasn't expected to delay Wednesday's debate on President Trump's Supreme Court nominee Judge Neil Gorsuch or Thursday's votes.

The Senate voted on Tuesday afternoon to formally start debate, leading up to the expected vote later in the week.

Senate Democrats have secured enough votes to filibuster Gorsuch. Forty-two Democrats have said they will vote to block his nomination. Sen. Chuck Schumer, D-N.Y., one of Gorsuch's most vocal critics, said the nominee did little to win support during his confirmation hearings.

The facts in this case are simple: Gorsuch counts 55 supporters in the Senate: the 52 Republicans, along with three moderate Democrats— Joe Manchin of West Virginia, Heidi Heitkamp of North Dakota and Joe Donnelly of Indiana.

As long as Republicans enact a rule change—famously called the “nuclear option”—it would lower the threshold to confirm Gorsuch from 60 to a simple majority. Republicans would have the votes and Gorsuch would be confirmed.

The divide on Gorsuch's nomination is deep. Senate Republicans see him as a fair jurist, while Democrats see him as in the pockets of big companies.

Gorsuch, 49, is a 10-year veteran of a federal appeals court in Denver, where he's compiled a highly conservative record.

Sen. Chuck Grassley, R-Iowa, told Fox News’ “The First 100 Days” Monday that “Gorsuch is going to be on the Supreme Court by midnight Friday night. I can assure you that. One way or the other, he’s going to get the necessary votes to get there."

Senate Majority Leader Mitch McConnell on Tuesday said Democrats have hit a “new low” in their obstruction. He still has said that he would employ the nuclear option and has filed a motion for cloture-- the first step in invoking the nuclear option.

He reportedly said he would not end the 60-vote threshold on legislation while majority leader. The Senate will vote to invoke cloture on Thursday. Sixty votes are needed to invoke cloture, and McConnell will likely come up short.

Senate Democrats have continued to hit the Trump pick.

“There’s a reason they call it the ‘nuclear option,’ and that is that there’s fallout. And this fallout will be dangerously and perhaps disastrously radioactive for the Senate in years to come,” Sen. Richard Blumenthal, D-Conn., told The Washington Post.