WASHINGTON (AFP) - US President Donald Trump said on Sunday (Sept 27) the Senate will "easily" confirm his Supreme Court nominee Amy Coney Barrett before the election, despite furious Democratic opposition to his bid to steer the court rightward for years to come.

Mr Trump has nominated Judge Barrett, a darling of conservatives for her religious views, to replace the late liberal justice Ruth Bader Ginsburg in a lifetime seat on the top court, potentially impacting some of the most partisan issues in America, from abortion to gun rights to healthcare.

His decision to push her nomination through just weeks before the tense and potentially disputed Nov 3 election, in which polls show he is the underdog, has galvanised Democrats, who are calling for the decision to be made by the winner of the vote.

His election rival, Democrat Joe Biden, has led the charge.

"The Senate should not act on this vacancy until after the American people select their next president and the next Congress," Mr Biden said on Saturday, just moments after Mr Trump announced Judge Barrett's nomination.

But Mr Trump expressed confidence on Sunday in an interview with Fox & Friends.

"I think we're going to have it done easily before the election," he said.

"I think it would be nice to do. Get it out of the way," he continued, adding: "We have plenty of time."

Barring a huge surprise, Republican senators, who have 53 out of 100 votes in the Upper House of Congress, are expected to confirm Judge Barrett.

Senate majority leader Mitch McConnell, a Republican, has already announced that a vote will be held "this year".