Following Friday's vote, Mr Trump tweeted that he was "very proud". Susan Collins of ME and Jeff Flake of Arizona voted yes, as did Democrat Joe Manchin of West Virginia. But he says in a statement he is casting his vote on "what is best for West Virginia".
Collins is expected to announce her decision in a speech on the Senate floor at 3 p.m. Friday.
Dianne Feinstein of California, the Judiciary Committee's top Democrat, said Kavanaugh's testimony at last week's dramatic hearing should "worry us all", citing what she called "a hostility and belligerence that is unbecoming" of a Supreme Court nominee.
The procedural vote came after senators reviewed supplemental FBI reports on interviews the bureau conducted into women's claims dating to high school and college.
On the floor, Senate Minority Leader Chuck Schumer said the Kavanaugh confirmation was the "shameful culmination of scorched-earth politics practiced by the hard right". "I believe Brett Kavanaugh's a good man".
Friday morning, Democratic Sen. Several criticized Republicans for limiting the FBI investigation to just nine interviews.
Democrats have sought to block Kavanaugh's confirmation since soon after Trump nominated him in July.
Sen. Charles Grassley of Iowa, the Judiciary Committee chairman, said the documents were exculpatory as soon as he was briefed on them. Kavanaugh has denied all the charges. Chuck Schumer (D-New York) said.
Three of the four have to vote against Kavanaugh's nomination in order to sink it.
She added that with Supreme Court appointments lasting a lifetime, "Those who seek these seats must meet the highest standards in all respects, at all times". He said he would return to cast the decisive vote if needed.
All eyes have been on a handful of senators, including Collins, who were undecided on President Trump's U.S. Supreme Court nominee.
North Dakota Democrat Heidi Heitkamp announced she would vote against Kavanaugh. Jeff Flake from Arizona and Sen.
But the fight was defined in recent weeks by sexual assault accusations, especially Christine Blasey Ford's allegation that a drunken Kavanaugh tried to rape her at a 1982 high school gathering. "There were a few people interviewed and there were the people who were potential eyewitnesses to both incidents". Murkowski said she'd use an obscure procedure that lets one senator offset the absence of another without affecting the outcome, while letting the missing lawmaker's preference appear in the record.
"I would agree that the materials that I read did not provide direct corroboration, but there were a dozen, two dozen other witnesses who were not interviewed", Coons said. Her lawyer, Michael Avenatti, called the investigation illegitimate without an inquiry into Swetnick's claims.
Democrats and lawyers for Ford lambasted the FBI's report, calling it a whitewash micromanaged by Team Trump. Referring to Swetnick, Trump said: "This woman had no clue what was going on, and yet she made the most frightful charges".
Tensions were also reflected by the thousands of boisterous anti-Kavanaugh demonstrators who flowed around the Capitol complex for days, confronting senators and even reported near their homes.
The allegations against Kavanaugh prompted intense reactions at the height of the "Me Too" movement, divided along political and gender lines.
Coons agreed with Kavanaugh that "he said things that he should not have".