Supreme Court nominee Brett Kavanaugh survived a critical procedural vote in the Senate on Friday with help from Sens. Jeff Flake, R-Ariz., and Susan Collins, R-Maine, but his fate was still unclear as Collins said she would reveal at 3 p.m. whether she can support Kavanaugh in a final vote that's expected in the coming days.

The Senate voted 51-49 to end debate on the nominee, setting up a final vote on the nominee. But the vote came with surprises — Sen. Lisa Murkowski, R-Alaska, voted against Kavanaugh, but she was offset by Sen. Joe Manchin, D-W.Va., who voted with Republicans.

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The nomination is still on a knife's edge, given that Collins' final position is still not known, and Flake showed last week he has the potential to be flipped at the last minute.

Still, Sen. John Thune, R-S.D., said Republicans are confident they will have the minimum 50 votes needed to confirm Kavanaugh.

“We feel good,” Thune told reporters Friday. “Hopefully everybody stays on the team. I think that will be the case.”

Senate Majority Leader Mitch McConnell, R-Ky., called Kavanaugh “a nominee of the very highest caliber,” and he condemned “the absolutely disgraceful spectacle of the past two weeks,” which have included a string of accusations against Kavanaugh dating back to high school and college.

“There is abosolutely no corroborating evidence for these allegations,” McConnell said.

Senators voted to end debate on Kavanaugh’s nomination as police stepped up security around the U.S. Capitol and Senate office buildings in response to hundreds of protesters, most of them against Kavanaugh, who gathered in an effort to sway undecided GOP lawmakers and those most vocally in favor of him.

The vote came one day after the FBI delivered a 46-page report that detailed interviews with nine witnesses connected to two sexual misconduct allegations against Kavanaugh that date back 35 years.

Republicans said the report did not corroborate the accusations and lacked first-hand witness reports.

“I’m voting for confirmation because of the evidence and Judge Kavanaugh’s qualifications,” said Sen. Ben Sasse, R-Nebraska. “After spending more than 150 hours doing my homework, I completed my reading of the FBI’s seventh background investigation this morning.”

Democrats called the report incomplete and absent key witness interviews who could have helped bolster the allegations.

Collins, Flake, and Murkowski spent hours pouring over the report, which was locked in a secure reading room in the Capitol basement.

It included interviews pertaining to an accusation by Christine Blasey Ford, who said Kavanaugh attempted to sexually assault her at a party while the two were in high school. The FBI also talked to Deborah Ramirez, who said Kavanaugh flashed her at a party while the two were freshman at Yale University.

Ford testified about her claim at an emotional Judiciary Committee hearing last month. Kavanaugh responded with a fiery defense at the same hearing, attacking on Democrats over their handling of his nomination. Kavanaugh published an op-ed in the Wall Street Journal late Thursday conceding he may have been too emotional and proclaiming his judicial independence, in spite of that hearing performance.

Lawmakers debated Kavanaugh’s nomination Friday morning before voting.

Senate Judiciary Committee Chairman Chuck Grassley, R-Iowa, who presided over the confirmation hearing, said Kavanaugh was subjected to a “monstrous” campaign by “left-wing” operatives who wanted to keep a conservative pick off the bench.

“This should have been a respectable and dignified confirmation process,” Grassley said. “Before left-wing outside groups and Democratic leaders had them in their sights, Judge Kavanaugh possessed an impeccable reputation and was held in high esteem by the bench and bar alike.”

Grassley also condemned the role of protesters, which he said were trying to enforce “mob rule” by dictating the outcome of the confirmation process.

Grassley and other lawmakers have been accompanied by U.S. Capitol Police in recent days after several were approached by angry protesters near the Capitol.

Grassley’s counterpart on the Judiciary Committee, ranking member Dianne Feinstein, D-Calif., focused her closing floor speech on Kavanaugh’s record as a judge and her view he would likely vote to overturn Roe v. Wade, the high court ruling legalizing abortion.

“Judge Kavanaugh is not only willing to disregard precedent but his opinions fail to appreciate the challenging realities women face when making theses difficult decisions,” Feinstein said in a floor speech before the vote.

Feinstein also cited Kavanaugh’s “extreme view on guns,” and her belief that he is more than just “pro-gun,” and would push to further de-regulate gun ownership even as firearms become “more advanced and more dangerous.” She said Kavanaugh’s emotional and sometimes angry testimony at the hearing airing Ford’s accusation make him unsuitable for the Supreme Court.

“We saw a man filled with anger an aggression,” Feinstein said.

Feinstein also cited “serious and credible allegations,” by Ford and Ramirez in her decision to reject Kavanaugh.

“He would be a deciding vote on the most important issues affecting our country and every American for generations to come,” Feinstein said. ”Based on all the factors we have before us, I do not believe Judge Kavanaugh has earned this seat.”

The fight over Supreme Court nominees has been spiraling into partisan war for years, escalating after the 2016 death of Associate Justice Antonin Scalia. Former President Barack Obama nominated Merrick Garland to replace Scalia, but Majority Leader Mitch McConnell, R-Ky., refused to bring his nomination to the floor for a vote. The seat remained vacant until President Trump was elected and picked Neil Gorsuch.

Democrats remain bitterly angry over a seat they believe does not belong to the GOP and which has helped tilt the court to the right.

Senate Minority Leader Chuck Schumer, D-N.Y., on Friday called the the Kavanaugh nomination process “a sorry epilogue to the brazen theft of Justice Scalia’s seat.”