Democrats held the line on a controversial appeals court nominee Thursday and denied victory to Senate Majority Leader Bill Frist (R-Tenn.), at least for now.

Despite the defection of four Democrats, the cloture motion to end debate and vote on Miguel Estrada’s nomination to the U.S. Court of Appeals for the D.C. Circuit failed 55-44.

Cloture motions require 60 votes to succeed.

Democratic Sens. John Breaux (La.), Zell Miller (Ga.), Bill Nelson (Fla.) and Ben Nelson (Neb.) voted with Republicans. Sen. Bob Graham (D-Fla.), who is recovering from heart surgery, did not vote.

Even though his party didn’t vote unanimously, Minority Leader Thomas Daschle (D-S.D.) said he was proud of his Caucus for hanging tough and is confident it would continue to hold together.

The vote sends the message “loud and clear” that Democrats will not allow a confirmation vote until Estrada provides more information about his views, Daschle said, noting that no job seeker would be hired if he or she left half the application blank.

“That will be our position regardless, however many votes are cast,” he said.

Frist promised to file endless cloture motions and force vote after vote until the Senate votes to either confirm or reject Estrada outright.

“This is just the beginning,” Frist said shortly after the late-morning vote. “We will not be satisfied … until we have a simple up-or-down vote.

“This is not going to deter us, not going to stop us and not going to slow us down,” he said.

Frist said he has been patient and allowed more than 100 hours of floor debate on the Honduran immigrant and Harvard Law School graduate since Feb. 5.

The Majority Leader added that Estrada has repeatedly made himself available to lawmakers and agreed to meet one-on-one with any Senator who asks.

But Daschle dismissed such meetings as only a “public relations ploy” unless Estrada is willing to answer all their questions.

Democrats have requested to see documents from cases Estrada argued as an assistant to the solicitor general. Additionally, they want Estrada to come before the Judiciary Committee again. A spokesman for Frist said it is up to Judiciary Chairman Orrin Hatch (R-Utah) to call another hearing.

Both sides claim they are trying to uphold the Constitution and carry out the Senate’s “advise and consent” mandate on judicial nominees.

Republicans say that Democrats’ filibuster of Estrada unfairly raises the bar by effectively requiring him to garner 60 votes for confirmation, instead of a simple majority.

“This is a very sad day for the Senate and a very sad day for the republic,” said Republican Conference Chairman Rick Santorum (Pa.), criticizing Democrats for politicizing the judicial process.

But Democrats say they are following the Founding Fathers’ will by trying to find out where Estrada stands on important issues. And that confirming Estrada without that information would reduce the Senate to a rubber stamp.

“It goes to the heart of the Constitution — whether the Senate will play any meaningful role in the confirmation of judges,” Sen. Charles Schumer (D-N.Y.) said.