Bush said he will name a replacement for her "in a timely manner." The president cited the Senate's demand for confidential White House documents in explaining her withdrawal. He said such disclosures "would undermine a president's ability to receive candid counsel."

Commentators had said in advance of today's developments that a confrontation over White House papers related to Miers would present a face-saving reason to end her nomination.

"I am concerned that the confirmation process presents a burden for the White House and our staff that is not in the best interest of the country," Miers said in a letter to Bush.

Miers, 60, the White House counsel, fellow Texan and long- time Bush confidant, was named by Bush on Oct. 3 to succeed retiring Justice Sandra Day O'Connor. Miers never overcame doubts among conservative opinion makers and within Bush's political base about her powers of intellectual leadership and reliability on such issues as abortion, affirmative action, gay rights and school prayer.

"The reaction to her nomination has been so intense and sustained that the White House couldn't ignore it any longer," said Roger Pilon, director of the Center for Constitutional Studies at the libertarian Cato Institute in Washington, in an interview before the withdrawal. "Confirmation was doubtful.