Judge Brett Kavanaugh was sworn in as the 114th Supreme Court justice late Saturday, just hours after the Senate voted to approve President Trump's nominee to the nation's highest court after a rancorous confirmation battle.

Kavanaugh was sworn in by Chief Justice John Roberts in a private ceremony, accompanied by his wife and children. The ceremonial swearing in is expected to happen on Monday evening at the White House. It means that now-Justice Kavanaugh will begin hearing cases before the court on Tuesday.

The Senate voted 50-48 to confirm Kavanaugh, mostly along party lines, after a weeklong FBI probe helped settle concerns among most wavering senators about the sexual assault allegations that nearly derailed his nomination and led to a dramatic second hearing. Saturday’s roll call marked the tightest successful Supreme Court confirmation vote in over 100 years, closer than even that of Clarence Thomas who similarly faced sexual misconduct allegations.

Sen. Joe Manchin, D-W.Va., was the sole Democrat to vote “yes.” Sen. Lisa Murkowski, R-Alaska, was a “no,” but voted “present” as a courtesy to Sen. Steve Daines, R-Mont., who was attending his daughter’s wedding in Montana.

Democrats reacted to the vote by urging supporters to turn out to the polls in November for the midterms.

“The American people are raising their voices to a deafening roar today. We will not stop marching, we will not stop fighting, and we will vote on Election Day for leaders who share our values,” Democratic National Committee Chair Tom Perez said in a statement.

House Minority Leader Nancy Pelosi, D-Calif., said it was a "heartbreaking day for women, girls and families across America." She also announced she is filing a Freedom of Information Act request so the public can view documents connected to the FBI's background investigation into sexual assault allegations against Kavanaugh.

“The conduct of the Senate Republican Majority did violence to the reputation of both the Senate Judiciary Committee and the Supreme Court. We must proceed in a judicious manner to set the record straight and ensure that this never happens again,” she said.

Senate Majority Leader Mitch McConnell, R-Ky., brushed off criticism from Democrats and said it was "a good day for America and an important day for the Senate."

"We stood up for the presumption of innocence, we refused to be intimidated by the mob of people coming after Republican members at their homes and hallways," he said.

At a rally in Topeka, Kansas, President Trump hailed the confirmation as a "tremendous victory" and slammed Democrats for their treatment of Kavanaugh during the contentious confirmation hearing.

"What he and his family endured at the hands of Democrats is unthinkable. In their quest for power, the radical Democrats have turned into an angry mob, you saw that today with the screaming and shouting," he said, referring to protests outside the Senate and Supreme Court earlier in the day.

The confirmation vote was all but secured Friday night when undecided Sens. Manchin and Susan Collins, R-Maine, announced they would vote to confirm Kavanaugh, along with Sen. Jeff Flake, R-Ariz., who threw a curveball into the process when he requested the supplemental background probe last week as a virtual condition for support. Collins, on the Senate floor Friday, dismissed claims that Kavanaugh would be an extremist judge, and said the sexual assault allegations against Kavanaugh failed to meet the “more likely than not” standard.

The explosive battle over his seating as the ninth justice extended Saturday into the vote itself, with protesters shouting from the gallery and packing the Capitol and Supreme Court grounds – vowing to inflict payback against Republicans in November, and indicating Kavanaugh will be a lightning rod for years to come.

“A vote to confirm Judge Kavanaugh today is a vote to end this brief, dark chapter in the Senate’s history and turn the page toward a brighter tomorrow,” McConnell said ahead of the vote, over which Vice President Pence presided.

While emerging from his formal confirmation hearing largely unscathed, Kavanaugh faced a late burst of sexual assault allegations from multiple women from when he was in high school and college. At the hastily convened second hearing that also featured accuser Christine Blasey Ford, he furiously and at-times emotionally denied the claims and attacked Democrats and left-wing activists for their handling of the allegations.

Ford, though, maintained she was “100 percent” sure he groped her and tried to force himself on her at a high school party.

Democrats said the claims were credible and called for further investigation, or even for Kavanaugh to withdraw. Ford’s account represented just one battleground. After she first came forward, prodded into the public eye by press leaks, another woman, Deborah Ramirez, said Kavanaugh exposed himself to her when they were at Yale. Another still, Julie Swetnick, claimed he and his friend Mark Judge (also accused of being in the room during the Ford incident) were involved in or present at “gang” rapes. Kavanaugh and Judge adamantly denied it all.

While Kavanaugh’s confirmation sometimes looked in doubt, particularly after the testimony of Ford, Republicans and the White House rallied to Kavanaugh’s side -- pointing to alleged inconsistencies and also a lack of corroborating evidence on the part of the accusers. They also slammed Democrats, accusing them of politicizing the accusations and trying to destroy Kavanaugh.

“Boy, y’all want power. God, I hope you never get it. I hope the American people can see through this sham,” a visibly angry Sen. Lindsey Graham, R-S.C., told Democrats at last week’s hearing.

Republicans conceded to the demand for a limited FBI investigation by Sen. Flake last Friday. Democrats had been demanding such an investigation into the assault claims, but criticized this one as not being thorough enough even before it had finished earlier this week.

On the Senate floor Saturday, Sen. Mazie Hirono, D-Hawaii, said the investigation was not comprehensive, and was "a sham, a fig leaf for the Republicans to hide behind."

Democrats expressed concern not only about the sexual assault allegations, but also his judicial record, arguing that he would overturn Roe v. Wade and rule from the extreme right. Senate Minority Leader Chuck Schumer, D-N.Y., said Friday that Kavanaugh’s views are “deeply at odds with the progress America has made in the last century of jurisprudence and at odds with what most Americans believe.”

They also said they were troubled by his fiery attack on Democrats.

“This behavior revealed a hostility and belligerence unbecoming of someone seeking to be elevated to the Supreme Court,” Sen. Dianne Feinstein, D-Calif, said Friday.

Protesters and activists had been a ubiquitous presence on Capitol Hill in recent days. On Saturday approximately 1,000 protesters marched to the Capitol steps, chanting “November is coming.”

Republicans said that the fight had motivated the conservative base ahead of the November midterms. McConnell meanwhile, told the Washington Post that the Democratic and left-wing opposition was a "great political gift for us."

“I want to thank the mob, because they’ve done the one thing we were having trouble doing, which was energizing our base,” he said.

Kavanaugh replaces Justice Anthony Kennedy, who retired at the end of July and was known as the swing justice, although he often sided with the conservative side of the bench.

Fox News' Chad Pergram, Mike Emanuel, John Roberts and Lauren Lee contributed to this report.