Washington ? The White House has laid the groundwork to place more conservatives on the Supreme Court, scrutinizing the legal views of a shrinking list of candidates amid speculation that Chief Justice William Rehnquist soon will step down.

Keenly aware that a chapter of President Bush’s legacy is at stake, conservative and liberal advocacy groups are preparing for what both sides believe will be a bruising confirmation fight.

Experts expect that Rehnquist, who is battling cancer, will leave when the current court session concludes in June.

“The vacancy could come anytime after this Memorial Day weekend, we think,” said Sean Rushton, director of the conservative Committee for Justice, which has close ties to the White House counsel’s office.

“They have been winnowing the list down for some time now. I imagine they’re down to maybe three or five – a handful anyway – who are their first choices,” he said.

White House officials say it is inappropriate to discuss filling a vacancy that does not exist.

But those tracking the process say the counsel’s office has researched the resumes of prospective justices, their court opinions and their views about constitutional law.

Liberals hope Bush will fill his first vacancy with a centrist, a consensus candidate, instead of one who would please right-wing Republicans who were instrumental in the president’s re-election. But they know that may be wishful thinking.

Bush has shown he is willing to stick by his nominees. When Senate Democrats denied votes on 10 of his picks for the federal bench, the president did not back down. Instead, he sent the same group of conservatives back to the Senate. That set the stage for the showdown over the filibuster.

“On every occasion the president has chosen confrontation rather than consultation and consensus, so we assume it’s going to be confrontation one more time – or four more times, depending on what happens,” said Ralph Neas, director of the People for the American Way. The liberal group has worked to block several of President Bush’s appointments to the courts.