Sen. Chuck Grassley (R-Iowa) is moving to nix the blue slip for two of President Trump's judicial picks, sparking a showdown with Democrats over nominations.

Grassley announced on Thursday that he has scheduled Nov. 29 hearings for David Stras, Trump's nomination to be an appellate judge on the 8th Circuit, and for Kyle Duncan, nominated to serve the 5th Circuit.

"Today, I'm announcing that the Judiciary Committee will hold a hearing for two circuit court nominees, each of whom has one home state senator who has not returned a blue slip containing a positive endorsement," Grassley said from the Senate floor.

Stras's nomination has been in limbo since early September when Sen. Al Franken (D-Minn.) said he wouldn't turn in his blue slip because he has "grown concerned that if confirmed to the federal bench, Justice Stras would be a deeply conservative jurist."

Grassley noted that GOP Sen. John Kennedy (La.) had not returned a positive blue slip for Duncan, but has said he does not oppose having a hearing.

The Iowa senator argued that both nominees are "well qualified" and "deserve the Judiciary Committee's further consideration"

The "blue-slip" rule - a precedent upheld by Senate tradition - has historically allowed a home-state senator to stop a lower-court nominee by refusing to return a sheet of paper, known as a blue slip, to the Judiciary Committee.

But how strictly the precedent is upheld is decided by Judiciary Committee chairman and enforcement has fluctuated depending on who controls the panel.

The Congressional Research Service noted that under some committee chairmen, nominations have gotten a hearing even if a home state senator did not return a blue slip.

"Over the century of the use of the blue slip, different chairmen have used the blue slip in different ways," according to a Congressional Research Service report.

Conservatives have been pressuring senators to nix the blue slip, arguing Democrats are using the rulebook to be obstructionist.

Grassley's announcement was immediately praised by Senate Majority Leader Mitch McConnell (R-Ky.).

"I must say ... that he has outlined a sensible use of the blue slip, which involves consultation but does not lead to a one-senator veto of a nominee," McConnell said from the Senate floor.

McConnell said earlier this year that he thought the blue slip should be an indication of how a senator would vote, but not be allowed to blackball a circuit court nominee.

Grassley and his staff have been signaling that they were preparing to move forward with circuit court nominations if they felt like Democrats were using the blue slip to stonewall the president's picks.

"A blue slip policy allowing a single senator to block a nominee from even receiving Committee consideration is a more extreme example of a counter-majoritarian practice," said a memo released earlier this month by Grassley's staff.

But deciding to move forward with circuit nominees even if a home-state senator doesn't return a blue slip gets rid of one of few leverages Democrats still have to stop a nominee they disagree with.

Democrats did away with the 60-vote filibuster for lower-court nominees when they held the majority in 2013, and Republicans followed suit by ending the filibuster for Supreme Court nominees earlier this year.

"Today's decision is one that will define Charles Grassley's legacy. Instead of keeping his word and continuing a longstanding Senate practice based on comity and respect, Grassley broke his word of honor to Senator [Patrick] Leahy [D-Vt.], brushed aside years of his own statements in support of the blue slip process and buckled to the demands of Senator McConnell to turn the Senate Judiciary Committee into a rubber stamp for Donald Trump," Marge Baker, the executive vice president for People for the American Way, a liberal outside group, said in a statement.

Grassley argued during his floor speech that he hasn't changed his position and that he will keep the blue slip to force the Trump administration to consult with lawmakers.

"I won't allow the White House to just steamroll home state senators but, as I've said all along, I won't let the blue slip be abused," he said.

He noted he was less likely to move forward with district court nominees - who unlike circuit court picks only represent one state - over the objections of home state senators.

He added that he would generally continue the blue slip "courtesy," but Democrats can't use it to blackball a nominee.

"Some of my Democratic colleagues and left-wing outside groups mistakenly assert that the blue slip affords a home state senator veto power over a nominee. That is not true," Grassley said.

Leahy, who chaired the committee during most of the Obama administration, did not allow a nomination to move forward if a home state senator refused to return a blue slip.

Republicans used the blue slip to block 18 nominations under President Obama.

And every GOP senator, including McConnell and Grassley, sent a letter to Obama in 2009 warning that if they weren't consulted, and didn't approve of, nominees from their home states they wouldn't let them move forward.

"Despite press reports that the Chairman of the Judiciary Committee now may be considering changing the Committee's practice of observing senatorial courtesy, we, as a Conference, expect it to be observed, even-handedly and regardless of party affiliation. And we will act to preserve this principle and the rights of our colleagues if it is not," the entire caucus wrote in the letter.