The US Senate takes up the historic nomination on Monday of Judge Ketanji Brown Jackson to become the first Black woman to sit on the Supreme Court.

The Senate Judiciary Committee is to hold four days of confirmation hearings beginning on Monday for President Joe Biden's choice for the highest US court.

Senate hearings for Supreme Court nominees have become an acrimonious partisan battleground over the past few years between Republicans and Democrats.

"Every court appointment is significant because so many vital matters are decided there," said Larry Sabato, director of the University of Virginia's Center for Politics.

"Plus, many of these matters are hot-button social issues that move votes or motivate voters" such as abortion or gun rights, Sabato told AFP.

Jackson has been nominated to replace another liberal justice, 83-year-old Stephen Breyer, who is retiring, and her confirmation will not ultimately change the composition of the court, Sabato noted.

"The conservatives still have a 6-3 majority," he said. "That alone lowers the stakes and should make for a smoother confirmation."

Democrats have the votes -- if barely -- to confirm Jackson, a 51-year-old Harvard-educated jurist who once served as a federal public defender for indigent clients, if they stick together.

The 100-member Senate is evenly split 50-50 Between Democrats and Republicans and Democratic Vice President Kamala Harris holds the tie-breaking vote.

'Playing to the Republican base'

"Inevitably," Sabato said, "a few Republican senators will go after Jackson on a wide variety of topics."

"Not because they think they can derail her -- they can't -- but because they'll be playing to the Republican base," he said.

At the end of the day though, "Why upset the apple cart in a fight they can't win with a Black woman jurist who is unquestionably well qualified?" Sabato said.

What's more, several moderate Republican senators voted just a year ago to confirm Jackson to the US Circuit Court of Appeals.

Several Republican lawmakers have criticized Biden for following through on his election-year pledge to select an African-American woman for the court.

"Black women are, what, six percent of the US population?" said Texas Senator Ted Cruz. "He's saying to 94 percent of Americans, 'I don't give a damn about you.'"

Jackson has impeccable credentials, however, and another Republican senator, Susan Collins of Maine, warned her colleagues to tread carefully.

"Given that Democrats, regrettably, have had some success in trying to paint Republicans as anti-Black, it may make it more difficult to reject a Black jurist," Collins said.

'Alarming pattern'

Although a frontal attack on Jackson could potentially backfire against Republicans seven months ahead of the midterm congressional elections, Senator Josh Hawley, a conservative from Missouri, has been laying the groundwork.

"I've noticed an alarming pattern when it comes to Judge Jackson's treatment of sex offenders, especially those preying on children," Hawley said in a series of tweets. "This is a disturbing record."

Hawley's comments drew a rebuke from White House deputy press secretary Andrew Bates.

"This is toxic and weakly-presented misinformation that relies on taking cherry-picked elements of her record out of context," Bates said, noting that Jackson has received the backing of several police unions, which tend to lean to the right.

Senator Mitch McConnell, the leader of the Republican minority in the Senate, dismissed Jackson's 2005-2007 experience as a public defender, which has been touted by her supporters.

"She and her allies credit her work as a public defender as helping her develop empathy," McConnell said. "I guess that means that government prosecutors and innocent crime victims start each trial at a disadvantage.

"If any judicial nominee really does have special empathy for some parties over others, that's not an asset, it's a problem," he said.

"President Biden is deliberately working to make the whole federal judiciary softer on crime," McConnell said, a charge Republicans are expected to use in the run-up to the November mid-term elections.

If confirmed, Jackson will be the third African-American to serve on the Supreme Court but the first Black woman.

Thurgood Marshall sat on the court from 1967 to 1991 and was succeeded by Clarence Thomas, who remains on the bench.