Judge John G. Roberts testifies before the Senate Judiciary Committee during his confirmation hearing to become the Chief Justice of the United States, on Capitol Hill in Washington.

The U.S. Senate is to vote Thursday on the nomination of Judge John Roberts to be the next chief justice of the United States. Confirmation is expected.

A number of Democrats have already announced they will join majority Republicans in voting for the nomination, assuring that Judge Roberts will be confirmed. Among them is Senator Joe Lieberman of Connecticut:

"I will vote to confirm Judge Roberts and send him off to the nonpolitical world of the Supreme Court with high hopes," Mr. Lieberman says.

But other Democrats, including Senator Ted Kennedy of Massachusetts, are concerned about Judge Roberts' record on abortion and civil rights when he worked as a lawyer in the Reagan administration, and they have signaled they will oppose the nomination.

"There is clear and convincing evidence that John Roberts is the wrong choice for Chief Justice," Mr. Kennedy says.

Judge Roberts says his work in the Reagan administration reflected the views of the administration.

For their part, Republicans, including Senator Mike Dewine of Ohio, have nothing but praise for the nominee:

"Judge Roberts is certainly one of the most accomplished legal minds of his generation," Mr. Dewine says.

Judge Roberts would succeed the late Chief Justice William Rehnquist.

Shortly after the confirmation vote, President Bush is expected to announce a nominee to succeed retiring Justice Sandra Day O'Connor.

Senators are expecting a much more difficult confirmation proceeding for next nominee.

Justice O'Connor often cast the deciding vote in close five-to-four rulings in controversial cases.

Senate Democrats are concerned that Mr. Bush may nominate a hard-liner to appeal to his conservative political base, and thus move the court to the right.

Although a new Supreme Court session begins Monday, Justice O'Connor has said she would stay on the bench until her successor is confirmed.