WASHINGTON (Reuters) - The American Bar Association on Tuesday gave U.S. Supreme Court nominee Sonia Sotomayor its top rating, boosting her anticipated confirmation as the first Hispanic justice on the highest U.S. court.

The ABA said its Standing Committee on the Federal Judiciary based its unanimous "well qualified" evaluation on a review of Sotomayor's professional integrity, competence and judicial temperament.

The ABA evaluation is certain to mentioned repeatedly by Sotomayor's backers at her confirmation hearing next week before the Senate Judiciary Committee.

A federal judge the past 17 years, Sotomayor is expected to win confirmation by the full Democratic-led Senate, perhaps overwhelmingly, to replace David Souter, who announced in May his retirement as a Supreme Court justice.

If confirmed, Sotomayor, 54, would likely not change the balance on the often divided nine-member court. Like Souter, she is seen as a liberal.

The ABA's Standing Committee on the Federal Judiciary rates the qualification of all federal court nominees.

"When the Judiciary Committee hearings to consider this nomination begin next week, Americans will hear from Judge Sotomayor herself, and I have the utmost confidence they will agree with the American Bar Association's review of her qualifications," said Senate Judiciary Committee chairman Patrick Leahy, a Democrat.

(Reporting by Thomas Ferraro, editing by Jackie Frank)