UPDATE 1-Trump says he thinks 2020 election will end up at Supreme Court

(Adds Trump quotes, background)

WASHINGTON, Sept 23 (Reuters) - President Donald Trump said on Wednesday he thinks the 2020 election will end up at the U.S. Supreme Court, adding that is why it was important to have nine justices.

Trump, speaking at an event at the White House, said Republican Senator Lindsey Graham, who chairs the Senate Judiciary Committee, would not even have to hold a hearing for the Supreme Court nominee and that the process would go quickly.

"I think this will end up in the Supreme Court and I think it's very important that we have nine justices," Trump said when asked if a full complement of justices was needed to handle any challenges to the Nov. 3 election between him and Democrat Joe Biden.

Trump has cast doubt on the integrity of the election, saying without evidence that the use of mail-in balloting during the coronavirus would lead to fraud.

"This scam that the Democrats are pulling, it's a scam, the scam will be before the United States Supreme Court, and I think having a 4-4 situation is not a good situation," he said.

Only one previous U.S. presidential election, the 2000 contest between Republican George W. Bush and Democrat Al Gore, had its outcome determined by the Supreme Court.

Trump is moving quickly to nominate a successor to liberal Justice Ruth Bader Ginsburg, who died on Friday, and his fellow Republicans in the Senate say they could hold a vote before the election. That would seal a 6-3 conservative majority on the court.

Trump has already appointed two conservatives to lifetime posts on the court, Neil Gorsuch in 2017 and Brett Kavanaugh in 2018. Supreme Court appointments require Senate confirmation, and Trump's fellow Republicans hold 53 of the chamber's 100 seats.

Senate Majority Leader Mitch McConnell has said he intends to act on any nomination Trump makes.

(Reporting by Jeff Mason and Eric Beech; Writing by Daphne Psaledakis; Editing by Sandra Maler and Peter Cooney)