Flake initially announced he would vote for Kavanaugh, but requested a week-long delay to allow the FBI to investigate allegations of sexual misconduct made against the 53-year-old judge.
While Democrats' defeat was all but certain, the Senate remained in session overnight, though the chamber was mostly empty.
In Washington, President Donald Trump said Saturday that he thought Collins was "incredible" and that she "gave an impassioned, attractive speech".
It represents the culmination of a decades-long project by the conservative movement to construct a like-minded majority on the Supreme Court which has been a defining and unifying cause in successive congressional and presidential campaigns. Republican senators echoed that idea, while Democratic senators repeatedly called for an FBI investigation into the allegations against Kavanaugh.
Senate leader Mitch McConnell said: "The court guards our right and the Senate guards the court". She then voted to advance Kavanaugh's nomination and has said that she will vote yes on Kavanaugh' during the full Senate's confirmation vote on Saturday.
"I have no doubt", Trump said, telling reporters that he had chosen Kavanaugh, in part, because "there's nobody with a squeaky-clean past like Brett Kavanaugh".
"I found Dr. Ford's testimony to be heart-wrenching, painful, compelling, and I believe that she believes what she testified to", Collins said. "The democrats have become too extreme and too unsafe to govern", Trump said. "We must always remember that it is when passions are most inflamed that fairness is most in jeopardy". A total of 164 people were arrested in the protests, U.S. Capitol Police said.
Collins, perhaps the chamber's most moderate Republican, proclaimed her support for Kavanaugh at the end of a floor speech that lasted almost 45 minutes. She added, "I give him my honest opinion and honest advice".
Manchin used an emailed statement to announce his support for Kavanaugh moments after Collins finished talking.
Trump said Thursday that "it is a very scary time for young men in America, where you can be guilty of something you may not be guilty of".More news: Chinese Foreign Ministry Revalidates Rejection to Illegal Entry US
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"Shame on you!" protesters yelled from the Senate gallery.
Republicans control the Senate by a meager 51-49 margin. Lindsey O. Graham (R-S.C.), one of Kavanaugh's most loyal defenders. "And I know it for a fact because I spoke with her, she didn't stop".
In their final summations, the two Senate party leaders reflected how bitter the divide had become. A few Democrats sat stone-faced nearby. She voted "present", balancing out Daines' absence. Lisa Murkowski fail to vote "yea" on the confirmation of Justice Brett Kavanaugh.
Hundreds were last night gathered outside the Supreme Court in Washington DC to protest against Kavanaugh's appointment. "And that is hard".
At a political rally in MS on Tuesday, Trump mocked Ford's account of what she says was a drunken attack on her by Kavanaugh when they were teenagers.
That support all but assures Republicans of the votes they need to push the nomination across the finish line. Similarly, Flake suggested he would vote "yes" for Kavanaugh "unless something big changes". Vice President Mike Pence presided over the roll call, but his potential tie-breaking vote unnecessary.
Kavanaugh's confirmation appeared to be in trouble a week ago, when three Republican senators, along with Democrats, demanded a supplemental FBI investigation into allegations brought against the nominee by women, including psychology professor Christine Blasey Ford and his former Yale University classmate Debbie Ramirez. That reflected Democrats' lasting umbrage over Republicans' 2016 refusal to even consider Merrick Garland, Obama's nominee to replace the late Antonin Scalia. But each of those cases has been carefully made a decision to protect the court's integrity from challenges that the conservatives are helping the political party they are affiliated with.
Two other women later emerged with sexual misconduct allegations from the 1980s.
The ferocious nature of the confirmation battle could also have an impact on the Court itself, as Kavanaugh's vehement and politicized defense of his own behavior raised questions about his temperament and whether he could genuinely be a honest broker and implementer of the law in the most sensitive cases.