Democrat challenger Joe Biden has accused president Donald Trump of abusing his power over plans to replace the late Supreme Court Justice and liberal icon Ruth Bader Ginsburgh - who died on Friday aged 87 - before the upcoming US election.
Just 24 hours after Ginsburg passed away, the president released a statement outlining his intention to find a replacement ahead of November's poll, a move that has enraged Democrats and threatens to reshape the highest court in the land for a generation.
Mr Trump, backed by Republicans, said he plans to appoint a female conservative justice, which would decisively tilt the ideological balance of power in the Supreme Court. As things stand, there are five Republican Supreme Court Justices and four alinged with the Democrats.
Speaking at an event in Philadelphia on Sunday, Mr Biden said the president's decision to press ahead with replacing Ginsburg was an abuse of executive power, adding that voters voices "should be heard" before any appointment is made.
"The United States Constitution was designed to give voters one chance, one chance to have their voice heard in who serves on the court. And by the way, there’s no court session between now and the end of this election," Mr Biden told a crowd at the Philadelphia Constitutional Center.
"That moment is now for the voters to get a chance to be heard, and their voice should be heard. And I believe voters are going to make it clear. They’ll not stand for this abuse of power, this constitutional abuse," he added.
The ideological make-up of the Supreme Court is crucial to its rulings on some of the most important and fiercely contested issues in US law, such as reproductive rights, voting rights, protections from discrimination, the power of the presidency, the rights of immigrants, tax rules and laws, and healthcare for millions of the most at-risk Americans.
Shortly after the president announced his move to replace Ginsburg before the election, Senate leader Mitch McConnell confirmed that he would be prepared to accept a nomination. However, Republicans have a slim majority of 53-47 in the Senate, meaning a few rebels could de-rail the plans. But there is still a very real chance the president could push through a replacement.
Democrats argue that Mr McConnell should follow the precedent set in 2016 when he refused to consider then-president Barack Obama’s nominee months before the election, eventually preventing a vote on Judge Merrick Garland.
On Saturday, Mr Trump took to the stage at a campaign rally in Fayetteville, North Carolina, to chants of “fill that seat”. He said it was his constitutional right to appoint a successor for Ginsburg, adding: “I will be putting forth a nominee next week. It will be a woman.”
Attorneys Barbara Lagoa (Atlanta), Amy Coney Barrett (Chicago) and Kate Comerford Todd (deputy White House counsel) are among Mr Trump's most favoured candidates to replace Ginsburg.
As the Senate returns to Washington on Monday, all eyes will be on Republicans Mitt Romney of Utah and Chuck Grassley of Iowa for clues to whether Mr Trump and Mr McConnell will be able to confirm Ginsburg's replacement anytime soon.
During Sunday's speech, Mr Biden urged unnamed Republicans to join senators Lisa Murkowski of Alaska and Susan Collins of Maine in opposing a confirmation vote before the election. It takes four GOP senators breaking ranks to keep Trump's nominee off the court.
"Uphold your constitutional duty, your conscience," said Biden, speaking in Philadelphia on Sunday. "Let the people speak. Cool the flames that have engulfed our country."
Despite Mr Biden's urging, there was little chance of calm in the election campaign as early voting progressed and the death toll from coronavirus neared 200,000.
Just before Ms Murkowski joined Ms Collins, House speaker Nancy Pelosi referred to the House having "options" in attempting to thwart the president's move. Mr Biden has also said he could make changes to the Supreme Court if elected to office.
"We have arrows in our quiver that I'm not about to discuss right now," speaker Pelosi said Sunday on ABC's "This Week." The House has no formal role in the confirmation of Supreme Court justices. But Pelosi would not rule out a new round of impeachment proceedings that might divert the Senate's attention.
Additional reporting by Associated Press