Updated at 3:35 p.m. ET

On the final day of the confirmation hearings for Judge Neil Gorsuch, the Senate Democratic leader announced his opposition to the Supreme Court nominee.

In a speech on the Senate floor, Chuck Schumer said Gorsuch "will have to earn 60 votes for confirmation," setting up a showdown with Republican leaders who may attempt to change Senate rules.

Republicans control 52 Senate seats and would need eight Democrats to join them to move Gorsuch's nomination forward under current Senate rules. Short of that, Republican Senate leaders may trigger the so-called nuclear option, changing the rules to allow a simple majority to proceed.

Schumer said Gorsuch "was unable to sufficiently convince me he'd be an independent check" on President Trump. He said Gorsuch was not "a neutral legal mind, but someone with a deep-seated conservative ideology."

Addressing Republicans, Schumer said if Gorsuch "cannot earn 60 votes, a bar met by each of President Obama's nominees and George Bush's last two nominees, the answer isn't to change the rules. It's to change the nominee."

Democrats changed Senate rules in 2013 to require a simple majority on most presidential nominees, but they left in place the supermajority requirement for Supreme Court nominees.

Progressive groups have been urging Democrats to uniformly oppose all of Trump's nominees. But several are facing tough re-election campaigns next year in states that Trump won in November. One of them, Bob Casey of Pennsylvania, announced Thursday he will oppose Gorsuch, saying he does not think "Judge Gorsuch's judicial approach will ensure fairness for workers and families in Pennsylvania."

Democrats have expressed frustration with Gorsuch's testimony before the Judiciary Committee, in which he sidestepped most of their questions aimed at getting a sense of how he might rule on the high court. Many are also still angry that President Obama's nominee for the vacancy created by Justice Antonin Scalia's death, Judge Merrick Garland, was never given a hearing by Republicans.

If enough democrats join Schumer in attempting to block Gorsuch's nomination, at least one Republican seems ready to go nuclear. Sen. Lindsey Graham told The Mike Gallagher Show that he's willing to do "whatever it takes" to get Gorsuch on the court. Graham's comments were first reported by CNN.

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