By Thomas Ferraro

WASHINGTON (Reuters) - Republican Senator Lindsey Graham, an early critic of President Barack Obama's Supreme Court nominee Sonia Sotomayor, said Wednesday he will vote to confirm her as the first Hispanic on the top U.S. court.

Graham, who sharply questioned Sotomayor at her Senate confirmation hearing last week, said she was a good pick to replace retired Justice David Souter, one of four liberals on the court that often splits 4-5 in favor of conservatives.

"I think that Judge Sotomayor will not be any more liberal than him, and on some issues, quite frankly, may be more balanced," Graham said in a Senate speech. "Time will tell."

Sotomayor looks all but certain to be confirmed by the Senate Judiciary Committee next week and later by the full Democratic-led 100-member Senate. Several moderate Republicans have already said they will vote for her.

But Wednesday, Senator Jon Kyl became the third member of the Senate Republican leadership to announce he would vote against her.

"I have not been persuaded that Judge Sotomayor is absolutely committed to setting aside her biases," Kyl said in a Senate speech.

Graham, like many others, had zeroed in on Sotomayor's earlier comments that a "wise Latina" woman might reach a better decision than a white man.

Graham, who is white, had demanded an apology and said if he had made such a comment his political career would be over.

Testifying at her confirmation hearing, Sotomayor, a federal judge for 17 years, offered no apology but gave her explanation of the role of a judge.

"The process of judging is the process of keeping an open mind," Sotomayor said, adding that jurists must guard against internal prejudice.

(Reporting by Thomas Ferraro; editing by Vicki Allen)