WASHINGTON - US Senator John McCain on Monday announced that he will support an upcoming effort by his fellow Republicans to win Senate confirmation of Judge Neil Gorsuch to the Supreme Court by changing the chamber's rules in order to overcome Democratic opposition.

McCain, in remarks to reporters, said he had "no choice" but to go along with a change in rules ending a tradition of 60 votes in the 100-member Senate needed to advance Supreme Court nominees to a final vote. He said he would support the rule change "because we need to confirm Gorsuch".

In the past, McCain has strongly opposed such a change.

Democrats on Monday corralled enough support to hold up a Senate confirmation vote on US President Donald Trump's Supreme Court nominee but Republicans threatened to change the Senate rules to ensure conservative judge Neil Gorsuch gets the lifetime job.

The Senate Judiciary Committee voted 11-9 along party lines to send Gorsuch's nomination to the full Senate, setting up a political showdown this week between Trump's fellow Republicans and the opposition Democrats that appears likely to trigger a change in long-standing Senate rules to allow his confirmation.

Democrats, portraying Gorsuch as so conservative he is outside the judicial mainstream, have amassed 42 senators in support of a procedural hurdle called a filibuster requiring a super-majority of 60 votes in the Republican-led, 100-seat Senate to allow a confirmation vote.

The Senate's Republican leaders insist Gorsuch will be confirmed on the Senate floor on Friday regardless of what the Democrats do. Republicans hold a 52-48 Senate majority.

In the face of the filibuster, Senate Majority Leader Mitch McConnell would be expected to force a confirmation vote by having the Senate change its rules and allow for a simple majority vote for confirmation of Supreme Court justices, a move sometimes called the "nuclear option" that Trump favors.

Senate Democratic leader Chuck Schumer, leading the filibuster effort, said McConnell should have the "vision and courage to see past this impasse" and not "go nuclear", suggesting that Trump replace Gorsuch with a new consensus nominee chosen after meeting with Democrats.

Senate confirmation of Gorsuch, 49, would restore the nine-seat high court's conservative majority, fulfilling one of Trump's top promises during the 2016 presidential campaign.

Trump in January nominated Gorsuch, a conservative appeals court judge from Colorado. He could be expected to serve for decades.

On the Senate floor, McConnell called the Democratic strategy "a new low", saying there was no principled reason to oppose a judge as well qualified as Gorsuch.

He did not explicitly say he would use the "nuclear option," but several Republicans said that would happen. White House spokesman Sean Spicer said the decision would be McConnell's.

Judiciary Committee Republicans blasted Democrats for pursuing what they called the first "partisan filibuster" of a Supreme Court nominee - there was a successful bipartisan filibuster five decades ago against a Democratic president's nominee - and said it would come to naught because of the threatened rule change.

Gorsuch was nominated to fill a vacancy created by the February 2016 death of Justice Antonin Scalia.

Reuters