WASHINGTON - Four key U.S. Senate Republicans on Sunday questioned past statements and legal decisions by Judge Sonia Sotomayor but stopped short of threatening to derail her nomination to the Supreme Court.

Still, the review of Sotomayor may not go according to the Obama administration's preference for confirmation hearings in June, said Senator Patrick Leahy, the Democratic chairman of the Senate Judiciary Committee.

I will meet my timetable. It could be different, Leahy told NBC's Meet the Press program.

Republican critics are focusing on remarks Sotomayor made in 2001 as Democratic defenders hail the 54-year-old federal appeals court judge as a fair-minded, highly qualified and historic nominee.

If confirmed by the Senate, Sotomayor would be the first Hispanic on the highest U.S. court and only the third woman. President Barack Obama, a Democrat, nominated her on Tuesday.

The ideological balance of the nine-member Supreme Court -- which decides on hot-button social issues such as abortion -- is not likely to change with the selection of Sotomayor, who would replace retiring Justice David Souter, also a liberal.

Senator Jeff Sessions, a member of the Judiciary Committee, said it was unlikely that Republicans would use procedural delays to try to block a vote on Sotomayor by the full 100-member Senate, where Democrats have a 59-seat majority.

We'll have to see how these hearings play out. I feel like a filibuster should not be used readily and ought to be for extraordinary circumstances, Sessions told Meet the Press.

Senator John Cornyn, another Republican committee member, told ABC's This Week program it was premature to say whether a filibuster was possible.

Senate Republican Leader Mitch McConnell said it was too early to tell if a filibuster might be tried but did not rule it out.

We have no earthly idea whether that would be appropriate at some point in the process. We've got a lot of cases to read and a lot of background to check, McConnell said on CNN's State of the Union program.

ALLEGATIONS OF RACISM

Cornyn and Sessions, as well as fellow Republican Senator Lindsey Graham who spoke on Fox News Sunday, said they were disturbed by a comment made by Sotomayor that a Latina judge would more often than not reach a better conclusion than a white male who hasn't lived that life.

Conservatives such as former House of Representatives Speaker Newt Gingrich and radio host Rush Limbaugh have accused Sotomayor of racism based on the 2001 remark.

I don't think she's a racist, said Graham, but he added he found Sotomayor's words troubling.

I hope she'll apologize. If I had said something like that, or someone with my background and profile, we wouldn't be talking about this nomination going forward.

Asked if a full Senate vote on Sotomayor could happen before the congressional recess in August, Graham said: I don't think that's practical and I don't think that's appropriate.

Obama and his aides said on Friday the 2001 comment was being taken out of context and that Sotomayor merely meant to make the point that varied life experiences can give judges valuable insights into cases.

Democratic Judiciary Committee member Senator Arlen Specter disagreed on the timing of Sotomayor's review and defended the nominee.

She has a long, solid record to show that she's fair and not biased, he said. It could be done by the end of the July session. I think it's important to have her on the bench when the court starts to consider in September ... what cases they're going to hear.

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