WASHINGTON — The Senate is expected to confirm President Biden’s Supreme Court nominee, Judge Ketanji Brown Jackson, on Thursday, securing her place as the first Black woman on the high court and giving Mr. Biden a bipartisan endorsement for his historic pick.

Three Republican senators have said they will support Judge Jackson, who would replace Justice Stephen Breyer when he retires this summer. While the vote will be far from the overwhelming bipartisan confirmations for Justice Breyer and other justices in decades past, it will still be a significant bipartisan accomplishment for Mr. Biden in the narrow 50-50 Senate after GOP senators aggressively worked to paint Judge Jackson as too liberal and soft on crime.

“It will be a joyous day,” said the majority leader, Senator Schumer, as he announced Thursday’s vote late Wednesday evening. “Joyous for the senate, joyous for the Supreme Court, joyous for America.”

Judge Jackson, a 51 year-old federal appeals court judge, would be just the third Black justice, after Justices Thurgood Marshall and Clarence Thomas, and the sixth woman. She would join two other women, Justices Sonia Sotomayor and Elena Kagan, on the liberal side of a 6-3 conservative court. With Justice Amy Coney Barrett sitting at the other end of the bench, four of the nine justices would be women for the first time in history.

After a bruising hearing in which Republicans on the Senate Judiciary Committee aggressively interrogated Judge Jackson on her sentencing record, three GOP senators came out and said they would support her. The statements from Senators Collins, Murkowski and Romney all said the same thing — they might not always agree with Judge Jackson, but they found her to be enormously well qualified for the job.

Ms. Collins and Ms. Murkowski both decried the increasingly partisan confirmation process, which Ms. Collins called “broken” and Ms. Murkowski called “corrosive” and “more detached from reality by the year.”

Mr. Biden, a veteran of a more bipartisan Senate, said from the beginning that he wanted support from both parties for his history-making nominee, and he invited Republicans to the White House as he made his decision. It was an attempted reset from three brutal Supreme Court battles during President Trump’s administration, when Democrats vociferously opposed the nominees, and from the end of President Obama’s, when Republicans blocked Supreme Court nominee Merrick Garland from getting a vote.

Before the Senate Judiciary Committee last month, Judge Jackson said her life was shaped by her parents’ experiences with lawful racial segregation and civil rights laws that were enacted a decade before she was born.

With her parents and family sitting behind her, she told the panel that her “path was clearer” than theirs as a Black American. Judge Jackson attended Harvard University, served as a public defender, worked at a private law firm and was appointed as a member of the United States Sentencing Commission in addition to her nine years on the federal bench.

“I have been a judge for nearly a decade now, and I take that responsibility and my duty to be independent very seriously,” Judge Jackson said. “I decide cases from a neutral posture. I evaluate the facts, and I interpret and apply the law to the facts of the case before me, without fear or favor, consistent with my judicial oath.”

Once sworn in, Judge Jackson would be the second youngest member of the court after Justice Barrett, 50. She would join a court on which no one is yet 75, the first time that has happened in nearly 30 years.

Judge Jackson’s first term will be marked by cases involving race, both in college admissions and voting rights. She has pledged to sit out the court’s consideration of Harvard’s admissions program since she is a member of its board of overseers. But the court could split off a second case involving a challenge to the University of North Carolina’s admissions process, which might allow her to weigh in on the issue.

Republicans spent the hearings interrogating her sentencing record on the federal bench, including the sentences she handed down in child pornography cases, which they argued were too light. Judge Jackson pushed back on the GOP narrative, declaring that “nothing could be further from the truth” and explaining her reasoning in detail. Democrats said she was in line with other judges in her decisions.

The GOP questioning in the Judiciary committee stuck for many Republicans, though, including the majority leader, Senator McConnell, who said in a floor speech Wednesday that Judge Jackson “never got tough once in this area.”

Democrats criticized the Republicans’ questioning.

“You could try and create a straw man here, but it does not hold,” said Senator Booker at the committee’s vote earlier this week. The panel deadlocked on the nomination 11-11, but the Senate voted to discharge it from committee and moved ahead with her confirmation.