President Donald Trump has selected Judge Amy Coney Barrett, the favorite candidate of conservatives, to succeed Justice Ruth Bader Ginsburg and will try to force Senate confirmation before Election Day in a move that would significantly alter the Supreme Court's ideological makeup.

Trump plans to announce Saturday that she is his choice, according to six people close to the process who asked not to be identified. As they often do, aides cautioned that Trump sometimes upends his own plans.

But he is not known to have interviewed any other candidates and came away from two days of meetings with Barrett this week impressed with a jurist he was told would be a female Antonin Scalia, referring to the justice she once clerked for. On Friday night, Barrett was photographed getting out of her car outside her home in South Bend, Ind.

"I haven't said it was her, but she is outstanding," Trump told reporters who asked about the judge's imminent nomination after CNN and other news outlets reported on his choice.

Trump's political advisers hope the selection will energize his conservative political base in the thick of an election campaign in which he has for months been trailing former Vice President Joe Biden. But it could also rouse liberal voters afraid that her confirmation could spell the end of Roe v. Wade, the decision legalizing abortion, as well as other rulings popular with the political left and center.

The nomination will kick off an extraordinary scramble by Senate Republicans to confirm her for the court in the 38 days before the election on Nov. 3, a scenario unlike any in U.S. history. While other justices have been approved in presidential election years, none has been voted on after July. Four years ago, Senate Republicans refused to even consider President Barack Obama's nomination to replace Scalia with Judge Merrick Garland, announced 237 days before Election Day, on the grounds that it should be left to whomever was chosen as the next president.

In picking Barrett, a conservative and a hero to the anti-abortion movement, Trump could hardly have found a more polar opposite to Justice Ginsburg, a pioneering champion of women's rights and leader of the court's liberal wing. The appointment would shift the court's center of gravity considerably to the right, giving conservatives six of the nine seats and potentially insulating them even against defections by Chief Justice John Roberts, who on a handful of occasions has sided with liberal justices.

Trump made clear this week that he wanted to rush his nominee through the Senate by Election Day to ensure that he would have a decisive fifth justice on his side in case any voting disputes reached the high court, as he expects they will. He has repeatedly made baseless claims that the Democrats are trying to steal the election and appears poised to challenge any result in which he doesn't win.

Majority Leader Mitch McConnell has enough votes to push through Judge Barrett's nomination if he can make the tight time frame work. Republicans are looking at holding hearings before the Senate Judiciary Committee the week of Oct. 16 and a floor vote by late October.

Democrats have expressed outrage at the rush and accused Republicans of rank hypocrisy given their treatment of Judge Garland, but they have few options for slowing the nomination, much less stopping it. Instead, they have focused on making Republicans pay at the ballot box and debated ways to counteract Trump's influence on the court if they win the election.