However, she said while she would vote "no" on Saturday, she would ask that her vote be registered as "present" so as not to jeopardize the majority - and allow a fellow Republican to attend his daughter's wedding instead of returning to Washington to vote.
Grassley later returned to the reporters to clarify his remarks, adding that it was also hard to recruit male senators.
In the end, Collins and Murkowski diverged.
Senator Cory Booker of New Jersey, one of the Democrats who voted against the motion and has vocally opposed Kavanaugh's nomination since accusations of sexual assault arose in July, lamented the vote's passing on CNN.
Judge Kavanaugh's confirmation would tilt America's highest court in favour of conservatives.
But his ascent to the Supreme Court was in serious doubt last week after research psychologist Christine Blasey Ford testified that he had sexually assaulted her at a Washington area party in the early 1980s.
Murkowski chose the opposite path.
Joe Manchin was also confronted by protesters on October 5, 2018, who demanded he oppose Kavanaugh's nomination.
Collins wasn't the only senator to announce a plan to vote yes in the full vote tomorrow.
"I believe that Brett Kavanaugh is a good man, I believe he is a good man", she said. You do not get to say you believe her, but not that part.
He called Sen. Susan Collins' (R-Maine) Friday floor speech describing Kavanaugh's accomplishments and Democrats' obstruction "outstanding".
In the Capitol, however, both senators won praise from their colleagues.
Heitkamp said she was troubled by Kavanaugh's aggressive appearance before the Senate Judiciary Committee and the message his confirmation would send to women and girls across the country. Flake said he saw no additional corroborating information against Kavanaugh, although he was "still reading" it. John McCain voted in favor of cloture on last year's Affordable Care Act repeal but ultimately voted against the bill. "I know that it's disturbing that she's the only one willing to vote no".
The Alaska senator was the only Republican Friday to vote against moving forward on Kavanaugh, calling it a "very, very difficult" decision. And she still stuck to her conscience.
That this long, bitter saga ended on such a close vote with any suspense at all is a testament to the anti-Kavanaugh sentiment that kept all but one of the Democrats up for reelection this year in opposition to him-and to the ruthlessness of Republicans in rushing to a vote the minute a cursory FBI investigation of allegations against Kavanaugh was completed.
Kavanaugh faces multiple allegations of sexual misconduct, which have sparked a fierce, highly partisan battle over his nomination in recent weeks.
Eliza Collins of USA TODAY contributed to this article.
That would let Kavanaugh win by the same two-vote margin he'd have received had both senators voted. White House spokesman Raj Shah said the Trump administration was "fully confident" Kavanaugh had the necessary support.
Kavanaugh's confirmation would likely swing the court rightward in its judicial leanings - but that's not what protesters have been most concerned with Friday. But he said he will because he considers Kavanaugh a "qualified jurist who will follow the Constitution". And to cut them off in the Senate, you need 60 votes to do it.
Friday morning's vote officially gave the Senate 30 hours to debate the nomination.