Democrats Pledge More Intense Scrutiny of Roberts

Before the Senate acts on Roberts's new nomination, Kennedy said, the Senate has a right to know whom Bush intends to nominate for O'Connor's position. "The American people care deeply about the overall balance of their highest court."

With President Bush's approval ratings at an all-time low and his administration under fire over its handling of Hurricane Katrina, some conservatives are worried that Bush will forgo the chance to pick another conservative in favor of someone who will not provoke a fight.

Manuel Miranda, former legal counsel to Senate Majority Leader Bill Frist and the founder of a conservative group that follows judicial issues, said Bush must keep his campaign promise to nominate a justice in the tradition of conservative Justices Antonin Scalia and Clarence Thomas, or risk "sinking even lower in the polls."

"If anything is keeping him afloat right now, it's conservative support," Miranda said.

Meanwhile, Democrats on the Hill are feeling more emboldened by the president's weakened political standing, according to interviews with senior aides and Democratic strategists. Ron Klain, a former aide to President Bill Clinton, said Democrats may be more willing to fight a staunchly conservative second pick.

"As his poll numbers fall, his domestic problems accumulate, and as independent voters increasingly wonder if he is out of touch with what's going on in the country, then Democrats in conservative states have less to fear by crossing him," Klain said.

The question for Democrats is whether the American public, consumed with images of the devastation in the Gulf Coast states, will tune in to the nomination hearings.

Senators are treading carefully. Sen. Patrick J. Leahy (D-Vt.) said that the Senate looks forward to consulting Bush on a successor to O'Connor, a pick he stressed will "affect all of us, and the generations who follow us."

At the same time, he said, "these are not the only challenges facing the nation at this critical time. Most urgent at this moment is providing the necessary help to Americans still suffering in New Orleans and elsewhere along the Gulf Coast."