Washington  - President Barack Obama's nominee for the US Supreme Court, Sonia Sotomayor, confronted conservative opponents who accused her of racial bias during a testy first day of cross- examination Tuesday in the Senate.

Sotomayor, who would be the first Latino justice on the US Supreme Court, won praise from Obama's Democrats for her wide legal experience. But she was forced by opposition Republicans to answer for past comments that critics charge showed favouritism toward ethnic minorities.

The Senate Judiciary Committee's confirmation hearing, which began with opening statements on Monday, is expected to last at least until the end of the week. Sotomayor took questions for more than 6 hours on Tuesday and will be quizzed Wednesday by another eight senators.

Senators from both sides tried to probe Sotomayor's views on a whole host of sensitive political and legal issues in the United States. As with previous judicial nominees, she sidestepped most issues that have not already been decided by the highest US court.

She backed the Supreme Court's ruling last year that US citizens have a right to own guns, said that a 1973 ruling that establish a legal right to abortion was "settled law," and said that affirmative action was still necessary at times to achieve equality for racial minorities.

Sotomayor said she lamented a "misunderstanding" over a remark that has drawn the most controversy - that she hoped a "wise Latina," because of her life experiences, would more often than not reach a better decision than a white male. Sotomayor said the comment was intended to inspire Latino lawyers to enter the profession.

"I want to state upfront, unequivocally and without doubt, that I do not believe that any ethnic, racial or gender group has an advantage in sound judgement," Sotomayor told the committee. "I do believe that every person has an equal opportunity to be a good and wise judge regardless of their background or life experience."

Her comment came during an exchange with Senator Jeff Sessions, the top Republican on the committee, who slammed Sotomayor's judicial philosophy as "against the American ideal."

Republican Senator Lindsey Graham of South Carolina suggested a double standard: "If I had said anything like that, and my reasoning was that I'm trying to inspire somebody, they would have had my head."

Sotomayor's nomination has exposed sharp ideological differences in the Senate and wider divisions about the role of race in society. But with Democrats controlling 60 seats in the 100-member chamber, her confirmation appeared almost certain.

Conservatives focused much of their attacks on Sotomayor's belief that a judge's background or ethnicity will necessarily affect decision-making. Supporters argue that she is right to say that her own life experiences will add value to the highest US court.

Sotomayor, 55, is the daughter of Puerto Rican parents and grew up in a public-housing project in New York's South Bronx. Her father died when she was 9 years old.

Much of her family was in attendance in the hearing room.

Sotomayor seemed to distance herself from Obama, who nominated her in May. Obama has drawn criticism from conservatives for saying that "empathy" should be one factor in how a judge evaluates cases.

"It's not the heart that compels conclusions in cases," she said. "It's the law." (dpa)