WASHINGTON (BLOOMBERG) - US President Donald Trump has demanded a Senate vote for confirmation of Supreme Court nominee Brett Kavanaugh and praised his performance minutes after a hearing on sexual assault allegations against him.

Judge Kavanaugh's testimony "was powerful, honest, and riveting", Mr Trump said in a tweet.

"Democrats' search and destroy strategy is disgraceful and this process has been a total sham and effort to delay, obstruct, and resist. The Senate must vote!"

Dr Christine Blasey Ford, a California psychology professor, told the Senate on Thursday (Sept 27) that Judge Kavanaugh sexually assaulted her while they were both in high school. She said she is "one hundred per cent" certain Judge Kavanaugh is the one who attacked her.

Judge Kavanaugh tearfully and "unequivocally" denied sexually assaulting Dr Ford.

He accused Democrats on the Senate Judiciary Committee of dragging out his confirmation and turning the process into "'a national disgrace".

Judge Kavanaugh's appointment may now hinge on how his testimony and that of his accuser is assessed by a handful of Republican senators who so far have avoided taking a position on his confirmation, including Ms Susan Collins of Maine, Ms Lisa Murkowski of Alaska and Mr Jeff Flake of Arizona. Each said they wanted to watch the hearing before making up their minds.

She told of fearing she would die as she was pinned to a bed, her mouth covered to keep her from screaming.

She said the 1982 incident - including the "uproarious laughter" of Judge Kavanaugh and his friend who she says witnessed the attack - was "seared into my memory" even though she didn't remember all the details.

Judge Kavanaugh repeatedly flashed his anger at Democrats on the panel, scowling, arguing with them and jabbing his finger toward the table in front of him.

"This whole two-week effort has been a calculated and orchestrated political hit, fuelled with apparently pent-up anger about President Trump and the 2016 election, fear that has been unfairly stoked about my judicial record, revenge on behalf of the Clintons and millions of dollars in money from outside, left-wing opposition groups," Judge Kavanaugh told the committee. "This is a circus."

The Judiciary Committee is scheduled to vote on Judge Kavanaugh's nomination on Friday, and the full Senate could act as early as next week.

The outcome and how the American public perceives it could redefine the "Me Too" era and affect the fight for control of Congress in the Nov 6 election.

"I was not at the party described by Dr Ford," Judge Kavanaugh said as he tried to save his nomination in the face of public claims of sexual misconduct by three women.

Dr Ford said she was pushed into a bedroom and attacked while attending a small gathering.

Democratic Senator Dick Durbin of Illinois challenged Judge Kavanaugh to ask the White House to order the FBI to question other witnesses about Dr Ford's allegations against him, a suggestion rejected by Mr Trump and Senate Republicans.

"You know that's a phony question because the FBI doesn't reach conclusions," Judge Kavanaugh responded.

Soon afterward, GOP Senator Lindsey Graham of South Carolina erupted in anger.

"What you want to do is destroy this guy's life, hold this seat open and hope you win in 2020," he said, pointing angrily at his Democratic colleagues. "This is the most unethical sham since I've been in politics."

Dr Ford told the committee that she's an independent person and "no one's pawn".

She said she was "terrified" to testify before the committee and that she "agonised daily" about whether to come forward with her claim.

Dr Ford said the attack occurred after she went upstairs to use the bathroom. She said she was pushed into a bedroom and onto a bed and that Judge Kavanaugh got on top of her. His friend was in the room and encouraged the attack, she said.

"I believed he was going to rape me," Dr Ford said.

Judge Kavanaugh put his hand on her mouth to keep her from screaming, she said, and because it was hard for her to breathe, "I thought that Brett was accidentally going to kill me."

She said the friend, who has denied any part in such an attack, jumped on them and she was able to escape.

Asked what she remembers from that night, Dr Ford responded: "The stairwell, the living room, the bedroom, the bed on the right side of the room as you walk into the room - there was a bed to the right - the bathroom in close proximity, the laughter - the uproarious laughter - and the multiple attempts to escape and the final ability to do so."

Judge Kavanaugh said Dr Ford's allegation is "refuted by the very people she says were there", who have said they don't recall the gathering.

A second woman, Ms Deborah Ramirez of Colorado, claims Judge Kavanaugh exposed himself to her at a drunken party when they were freshmen at Yale University.

And in the most lurid allegation yet, Ms Julie Swetnick of Washington said in a sworn statement released on Wednesday that Judge Kavanaugh took part in efforts during high school to get girls intoxicated so that a group of boys could have sex with them.

"The Swetnick thing is a joke, that is a farce," Judge Kavanaugh said at the hearing.

Republicans are trying to get Judge Kavanaugh, 53, confirmed as early as next week. Republicans hold a 51-49 advantage in the Senate and can't afford more than one defection to ensure confirmation without Democratic support.