Sen. Bernie Sanders called on his chamber's Republican majority on Sunday to keep existing rules allowing for the filibuster on Supreme Court nominations.
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The progressive Vermont Independent's comments to CNN's Dana Bash on "State of the Union" came a day after Vice President Mike Pence warned Democrats against blocking Judge Neil Gorsuch's nomination to the nation's high court.
"I certainly hope that the Republicans do not change the rules in order to push Gorsuch through," Sanders said.
This week, Senate Minority Leader Chuck Schumer announced his intention to filibuster Gorsuch's nomination. Under Senate rules, Republicans need 60 votes to end debate on Gorsuch's nomination and then a simple 51-vote majority to confirm him, but the GOP majority could modify those rules to end debate with a simple majority -- a change known as "the nuclear option."
In remarks in West Virginia on Saturday, Pence blasted Schumer for the move and promised that the Senate would get President Donald Trump's Supreme Court pick onto the court.
"President Trump and I are confident the United States Senate will confirm Judge Neil Gorsuch one way or the other," Pence said.
Sanders argued that the filibuster rule was appropriate for a position as important as Supreme Court justice and said a confirmation should come with some kind of bipartisan approval.
Despite having what he described as a "very pleasant" conversation with Gorsuch, Sanders said he was disappointed with his answers to questions on certain issues, such as campaign finance.
"If he does not get 60 votes, the Republicans owe the American people the obligation of bringing forward somebody who is more moderate," Sanders said.
Democrats, including the two independents who caucus with them, Sanders and Maine's Angus King, have 48 votes in the Senate to the Republicans' 52. The narrow GOP majority means the party would need at least 8 votes to overcome Schumer's filibuster.
When Democrats held the majority three years ago under the leadership of former Nevada Sen. Harry Reid, they invoked the nuclear option to remove the filibuster threat on most presidential appointments, although they kept the 60-vote bar for Supreme Court nominees.
In an interview with CNN in January, Schumer said he regretted that his party had done this.
Schumer pointed out Sunday that Democrats had left in place the filbuster for Supreme Court nominees and called on Senate Majority Leader Mitch McConnell to leave the rule in place.
"If the nominee can't get 60 votes, you don't change the rules, you change the candidate," Schumer said on ABC's "This Week."