The Republican-led senate has given Donald Trump the biggest win of his presidency so far by confirming his Supreme Court nominee despite fierce Democratic opposition and restoring a conservative majority.

The GOP have a 52-48 Senate majority and all of them supported Neil Gorsuch, 49, as did a handful of Democrats.

In the end the final vote was 54-45 in favour of Gorsuch's confirmation.

Gorsuch's confirmation ends the longest Supreme Court vacancy since 1862 during the American Civil War, with the court down a justice for almost 14 months since the death of Antonin Scalia in February 2016.

"He's going to make an incredible addition to the court," Senate Majority Leader Mitch McConnell said on the Senate floor.

Gorsuch could end up serving for decades and Trump may be able to have more influence on the court with three of the current justices aged 78 and over.

The expected confirmation would give a boost to Trump. The Republican-led Congress failed to pass legislation he backed to dismantle the Affordable Care Act, the healthcare law that was Democratic former President Barack Obama's signature legislative achievement. Courts also have blocked Trump's order to stop people from several Muslim-majority countries from entering the United States.

His administration also has faced questions about any role his associates may have played in Russian meddling in the 2016 US presidential election to help Trump.

Republicans on Thursday overcame a ferocious Democratic effort to prevent a vote by resorting to a Senate rule change known as the "nuclear option."

They disposed of long-standing rules to prohibit a procedural tactic called a filibuster against Supreme Court nominees.

That came after Republicans failed by a 55-45 vote to muster the 60-member super-majority needed to end the Democratic filibuster that had sought to deny Gorsuch confirmation to the lifetime post.

Gorsuch will be sworn into the Supreme Court on Monday 10 April.

Democratic minority leader Senator Charles Schumer spoke about the need to stop nuclear options becoming the norm in the senate. He said: "I hope the Republican leader and I can, in the coming months, find a way to build a firewall around the legislative filibuster, which is the most important distinction between the Senate and the House.

"Without the 60-vote threshold for legislation, the Senate becomes a majoritarian institution like the House, much more subject to the winds of short-term electoral change. No Senator would like to see that happen, so let's find a way to further protect the 60-vote rule for legislation."

House Speaker Paul Ryan said: "As we saw during his confirmation hearings, Judge Gorsuch is a thoughtful jurist who has the utmost respect for the rule of law. The Court—and the country—will benefit from his experience and his character.

"Justice Scalia's seat will now be filled by a judge committed to our Constitution and first principles. This is a good day for our country."

Senior Republican senator Lindsey Graham said: "I was proud to cast my vote in support of Judge Gorsuch for this important position. His confirmation is a victory for conservatives in South Carolina and across the United States.

"President Trump deserves a great deal of credit for selecting Judge Gorsuch. He was a homerun pick and President Trump could not have chosen a more qualified individual to serve on the highest court in the land."