Updated

Senate Republicans failed to end a Democratic block of President Bush's judicial nominee Thursday, dealing an expected — but not final — blow to Miguel Estrada's nomination.

The vote was 55-44, less than the three-fifths, or 60, votes needed to end debate on Estrada and set him up for an up-or-down vote.

Estrada, who was nominated in May 2001 for a seat on the U.S. Court of Appeals for the District of Columbia, would need only a simple majority in a straight vote on his confirmation.

Four Democrats voted to end debate on Estrada: Sens. Bill Nelson of Florida, John Breaux of Louisiana, Ben Nelson of Nebraska and Zell Miller of Georgia.

Independent Sen. Jim Jeffords of Vermont voted against Estrada. Sen. Bob Graham of Florida, still recovering from heart surgery, was absent.

After the vote, Bush issued a statement lamenting the outcome.

"Miguel Estrada is a well-qualified nominee to the U.S. Court of Appeals who has been waiting nearly two years for an up or down vote in the United States Senate. The decision today by 44 Senators to continue to filibuster and block a vote on this nomination is a disgrace," he said.

The vote came after nearly four weeks of heated debate over Bush's pick. If approved by the Senate, Estrada, who went before the Supreme Court on behalf of Bush after the disputed 2000 presidential election recount in Florida, would be the first Hispanic to sit on the circuit court bench.

Senate Majority Leader Bill Frist, R-Tenn., said Tuesday he intended to call "a series" of cloture votes on the nomination in the coming days and hoped to pressure certain members to siding with the GOP.

Frist said this cloture vote marks "only the beginning of the battle."

"If we need to, we will vote on cloture again and again," Frist said. "Let me be clear: the majority will press for an up-and-down vote on this nominee until Miguel Estrada is confirmed."

Senate Republican Conference Chairman Rick Santorum, R-Pa., on Tuesday predicted Republicans would lose and that at least one more vote to break the filibuster would occur next week.

But Senate Democratic Leader Tom Daschle of South Dakota, who stopped short of claiming a victory after Thursday's vote, warned that future votes will have the same result.

"Mr. Estrada holds positions that are extreme far-right ... that could be interpreted as ultra-far-right," Daschle said.

Senate Democrats have complained that Estrada has not been forthcoming about his own views and say they want more answers to their questions about his judicial philosophy.

The White House has offered to allow Estrada to meet with senators one-on-one for questions. A Justice Department official told Fox News that Sen. Blanche Lincoln, D-Ark., is the only Democrat to have submitted questions as of Thursday.

Daschle said he wants memos from Estrada's term as a deputy solicitor general in the Clinton Justice Department. Every living solicitor general — seven total — opposes turning over working memos.

"Meetings are nothing but a public relations ploy," Daschle said. "We've asked for two things — the answers to [our] questions and that he turn over documents ... anything short of that does not suffice."

Democrats have denied Republican charges that their actions are in any way hindering the work of the Senate. Frist said the Senate will continue with the business of the Senate. He will have to file a motion two days in advance if he wants another vote on Estrada.

The D.C. circuit — which decides important government cases involving separation of powers, the role of the federal government, the responsibilities of federal officials and the authority of federal agencies — currently has four Democratic appointees and four Republicans.

Only one judicial nominee has ever been stopped through a Senate filibuster: the nomination of Supreme Court Justice Abe Fortas to be chief justice in 1968. President Lyndon B. Johnson withdrew the nomination after the Senate rejected cloture.

Republicans say they will not withdraw Estrada's nomination.

Fox News' Tony Snow and Julie Asher and the Associated Press contributed to this report.