Republican members of the US Senate Judiciary Committee on Sunday questioned past statements and legal decisions by Judge Sonia Sotomayor who has been nominated to the Supreme Court.
If confirmed, Judge Sotomayor, 54, would be the first Hispanic and only the third woman to serve on the highest court in the United States.
President Barack Obama nominated the federal appeals court judge on Tuesday to replace retiring Justice David Souter.
He said he wanted to nominate someone who would bring empathy and a common touch to the court.
Democratic Party officials describe her as a fair-minded, highly qualified and historic nominee.
However, Republican critics are focusing on remarks she made in 2001: that a Latina judge "would more often than not reach a better conclusion than a white male who hasn't lived that life."
Senator John Cornyn, Senator Jeff Sessions and Senator Lindsey Graham said on Sunday they were disturbed by the comment.
Conservatives such as former House of Representatives Speaker Newt Gingrich and radio host Rush Limbaugh have accused her of "racism" based on the 2001 remark.
