Judge Kavanaugh denied the claim - and allegations that he drank to the point of memory loss at the time - in a feisty confrontation with senators.
All eyes are on several swing senators for Saturday's final vote. She later called the cloture vote "a mistake".
Murkowski, who is still considered an undecided vote on Kavanaugh's nomination, held private meetings with "dozens of Alaskan women" throughout the day on Thursday, according to MSNBC contributor Garrett Haake.
West Virginia's Joe Manchin is also planning to vote yes on Kavanaugh-the only Democrat to do so.
Under the pairing arrangement, the senator in the duo who is present and voting - in this case Murkowski - announces that she or he has "a pair" with the senator not in attendance.
There are few events that can pull a parent away from their own daughter's wedding, but for Republican Sen.
The FBI concluded its investigation into Kavanaugh late Wednesday night.
Keeping it dramatic, Murkowski said her "No" on Kavanaugh was one of the "most difficult" she has made in her political career.
She made the remarks hours after Sen.
The roll call vote is expected to begin at 3:30 p.m. ET.
After a bitter partisan fight that gripped the country, lawmakers backed Kavanaugh by 51 to 49 in a procedural vote that moved the Republican-controlled Senate toward a definitive decision on whether to confirm him. "The tactics have energized our base", he said, adding: "I want to thank the mob, because they've done the one thing we were having trouble doing, which was energizing our base".
"I will be a "no" tomorrow", Murkowski, an Alaska Republican, said on the Senate floor.
Republicans hold 51 seats in the Senate and changed Senate rules previous year to end filibusters for Supreme Court nominees.
The Friday cloture vote limits further debate and Democrats' ability to filibuster the final vote. Flake frustrated some in the GOP by siding with his Democratic colleagues and insisting that they should not have a full vote on Kavanaugh until there was a week-long FBI investigation into the sexual misconduct allegations against Kavanaugh.