Donald Trump refused to commit to a peaceful transfer of power if he loses the election, sparking further concern about the November 3 poll.
“We’re going to have to see what happens,” the president said when asked at a news conference.
Mr Trump repeated his mantra that the ballots being posted to millions of voters — to avoid having to vote in-person during the coronavirus pandemic — was an “out of control” disaster that would skew the result.
His comments came hours after he said he wanted the Senate to approve his upcoming Supreme Court nominee before the election because he believed the high court would have to rule on a contested result.
“This will end up in the Supreme Court, and I think it’s very important that we have nine justices,” Mr Trump said on Wednesday, amid rising concern that the result will not be clear immediately after the election.
Mr Trump will on Saturday announce his choice for the ninth seat on the high court, which became vacant following the death of Ruth Bader Ginsburg. Mitch McConnell, the Senate Republican majority leader, has said he would hold a vote on the nominee this year, but the Kentucky lawmaker has not made clear whether it would come before, or after, the election.
“I think it’s better if you go [hold a vote] before the election, because I think this scam that the Democrats are pulling . . . will be before the US Supreme Court,” Mr Trump told reporters at the White House on Wednesday.
In the clearest sign that he believes placing a conservative judge on the court before November 3 would help his political fortunes, Mr Trump said he wanted insurance against a 4-4 ruling.
“Having a four-four situation is not a good situation,” he said. “I think it should be eight-nothing, or nine-nothing. But just in case it would be more political than it should be . . . it’s very important to have a ninth justice.”
Five of the eight justices were appointed by Republican presidents. John Roberts, the chief justice who was appointed by George W Bush, has at times sided with the liberal wing, raising the possibility that the court could be deadlocked with a 4-4 ruling.
Mr Trump has refused to pledge that he would accept the result, as he accuses the Democrats of trying to engineer a “sham” election because of the expected rise in postal voting due to the coronavirus pandemic. Joe Biden, his Democratic rival, this week said he would accept the result.
Mitt Romney, the US senator from Utah and former Republican presidential nominee, slammed Mr Trump for refusing to commit to a peaceful transfer of power.
“Fundamental to democracy is the peaceful transition of power. Without that, there is Belarus,” he tweeted. “Any suggestion that a president might not respect this constitutional guarantee is both unthinkable and unacceptable.”
Some Republicans argue that holding a Senate confirmation vote on a new Supreme Court justice after November 3 would energise their voters to head to the polls. But others are keen to move more quickly to secure a reliably conservative bench for years to come.
The Republicans appear to have the votes to approve Mr Trump’s choice after Mr Romney, the only Republican senator to vote to impeach Mr Trump in February, signalled that he would not stand in the way.
Susan Collins and Lisa Murkowski — Republican senators from Maine and Alaska — have voiced opposition to voting before the election, but with a 53-47 majority in the chamber, the GOP should still have sufficient votes.
Ginsburg, a trailblazing justice who fought for equality and women’s rights and was only the second woman to sit on the Supreme Court, lay in repose at the court on Wednesday.
Bill Clinton, the former president who placed her on the bench in 1993, paid his respects at the Supreme Court on Wednesday, and Mr Trump is expected to follow suit on Thursday. On Friday Ginsburg will lay in rest in the US Capitol, becoming the first woman in history to receive that honour.
Follow Demetri Sevastopulo on Twitter