Amy Coney Barrett was confirmed as the newest member of the US Supreme Court by a deeply divided Senate on Monday, as Republicans overpowered Democrats to install President Donald Trump’s nominee only days before the election.

Ms Barrett’s confirmation will likely secure a conservative court majority for many years to come.

Mr Trump’s choice to fill the vacancy of the late liberal icon Ruth Bader Ginsburg potentially opens a new era of rulings on issues including abortion, the Affordable Care Act and even the president’s own re-election bid.

Democrats were unable to stop the confirmation of Mr Trump’s third justice on the court, as Republicans race to reshape the judiciary.

Ms Barrett is 48, and her lifetime appointment as the 115th justice will solidify the court’s conservative tilt.

“This is a momentous day for America,” Mr Trump said at a primetime swearing-in event on the South Lawn at the White House, where Justice Clarence Thomas administered the Constitutional Oath to Ms Barrett before a crowd of about 200 people.

Ms Barrett told those gathered she believes “it is the job of a judge to resist her policy preferences”, and vowed: “I will do my job without any fear or favour.”

In its timing, Monday’s vote was the closest high court confirmation ever to a presidential election, and the first in modern times with no support from the minority party.

The spiking Covid-19 crisis has hung over the proceedings. Vice President Mike Pence’s office said on Monday he would not preside at the Senate session unless his tie-breaking vote was needed after Democrats asked him to stay away when his aides tested positive for the coronavirus.

The vote was 52-48, and Mr Pence’s vote was not necessary.

“Voting to confirm this nominee should make every single senator proud,” said Senate Majority Leader Mitch McConnell, fending off “outlandish” criticism in a lengthy speech.

During a rare weekend session, Mr McConnell declared Ms Barrett’s opponents “won’t be able to do much about this for a long time to come”.

Democrats argued for weeks that the vote was being improperly rushed and insisted during an all-night Sunday session it should be up to the winner of the November 3 election to name the nominee.

However, Ms Barrett, a federal appeals court judge from Indiana, is expected to be seated swiftly and begin hearing cases soon.

Speaking near midnight on Sunday, Democratic senator Elizabeth Warren called the vote “illegitimate” and “the last gasp of a desperate party”.

Several matters are awaiting decision just a week before Election Day, and Ms Barrett could be a decisive vote in Republican appeals of orders extending the deadlines for absentee ballots in North Carolina and Pennsylvania.

The justices are also weighing Mr Trump’s emergency plea for the court to prevent the Manhattan District Attorney from acquiring his tax returns.

And on November 10 the court is expected to hear the Trump-backed challenge to the Obama-era Affordable Care Act.

Just before the Senate vote began, the court sided with Republicans in refusing to extend the deadline for absentee ballots in Wisconsin.

Mr Trump has said he wanted to swiftly install a ninth justice to resolve election disputes and is hopeful the justices will end the health law known as “Obamacare”.

During several days of public testimony before the Senate Judiciary Committee, Ms Barrett was careful not to disclose how she would rule on any such cases.

She presented herself as a neutral arbiter and suggested, “It’s not the law of Amy”. But her writings against abortion and a ruling on “Obamacare” show a deeply conservative thinker.

Republic senator Lindsey Graham, the chairman of the Judiciary Committee, praised the mother of seven as a role model for conservative women, saying: “This is historic.”

Republicans focused on her Catholic faith, criticising earlier Democratic questions about her beliefs. Mr Graham called Ms Barrett “unabashedly pro-life.”

At the start of Mr Trump’s presidency, Mr McConnell engineered a Senate rules change to allow confirmation by a majority of the 100 senators, rather than the 60-vote threshold traditionally needed to advance high court nominees over objections. That was an escalation of a rules change Democrats put in place to advance other court and administrative nominees under President Barack Obama.

Republicans are taking a political plunge by fast-tracking the confirmation just days from the November 3 election with the presidency and their Senate majority at stake.

Only one Republican — Senator Susan Collins, who is in a tight re-election fight in Maine — voted against the nominee, saying: “I do not think it is fair nor consistent to have a Senate confirmation vote prior to the election.”

Mr Trump and his Republican allies had hoped for a campaign boost, in much the same way Mr Trump generated excitement among conservatives and evangelical Christians in 2016 over a court vacancy.

That year, Mr McConnell refused to allow the Senate to consider then-President Barack Obama’s choice to replace the late Justice Antonin Scalia, arguing the new president should decide.