WASHINGTON (Reuters) — A fierce political battle was shaping up on Saturday over the selection of a successor to trailblazing liberal U.S. Supreme Court Justice Ruth Bader Ginsburg, with top Democrats opposing any move by President Donald Trump to nominate her replacement before the Nov. 3 presidential election.

Ginsburg, the senior liberal justice, died on Friday night at age 87 of complications from metastatic pancreatic cancer after 27 years on the court. Her death gives Trump a chance to expand the court’s conservative majority to 6-3 at a time of a gaping political divide in America.

Even as large crowds of mourners gathered outside the Supreme Court building well into the night to pay tribute to the iconic jurist, battle lines were forming. Supreme Court appointments require Senate confirmation, and Trump’s fellow Republicans control the chamber, holding 53 seats of the 100 seats. Democrats lack the votes to block any Trump nominee unless some Republican senators join them.

With the assistance of Senate Majority Leader Mitch McConnell, who has made confirmation of Trump’s federal judicial nominees a top priority, the president potentially could announce a nominee and move rapidly through the confirmation process, which usually takes at least two months.

Even before Ginsburg’s death, Trump had made public a list of potential nominees.

Trump’s Democratic opponent in the presidential race, Joe Biden, on Friday night said the winner of the election should be the one to make the selection and that Trump should not move forward with a nominee. Chuck Schumer, the Senate’s top Democrat, agreed.

McConnell pledged that the Senate would vote on any Trump nominee. Trump focused his initial remarks on praising Ginsburg, who he previously derided, without specifying his next steps.

For Democrats who considered her a heroine, the grief they have expressed over her death was tinged with fear over what happens next.

Conservative activists for years have sought to get enough votes on the Supreme Court to overturn the 1973 Roe v. Wade ruling that legalized abortion nationwide. During the 2016 campaign, Trump promised to appoint justices who would overturn that landmark decision. But the court in July, even with its conservative majority, struck down a restrictive Louisiana abortion law on a 5-4 vote.

The two justices who Trump already has appointed were Neil Gorsuch in 2017 and Brett Kavanaugh in 2018. Kavanaugh’s confirmation process was particularly heated, as he faced accusations by a California university professor, Christine Blasey Ford, that he had sexually assaulted her in 1982 when the two were high school students in Maryland. Kavanaugh angrily denied those accusations and was narrowly confirmed.

Confirmation votes could also put more pressure on incumbent Republican senators in highly competitive election races, including Maine’s Susan Collins and Arizona’s Martha McSally, at a time when Democrats are eyeing a chance to win control of that chamber. Alaska Senator Lisa Murkowski also could play a pivotal role.

Democrats are still seething over the Republican Senate’s refusal to act on Democratic President Barack Obama’s Supreme Court nominee, Merrick Garland, in 2016 after conservative Justice Antonin Scalia died during that election year. McConnell in 2016 said the Senate should not act on a court nominee during an election year, a stance he has since reversed.

Many court-watchers expect Trump to attempt to replace Ginsburg with a woman. One possible contender on Trump’s list is Amy Coney Barrett, a conservative judge on the Chicago-based 7th U.S. Circuit Court of Appeals who was under consideration in 2018 before Trump picked Kavanaugh.