WASHINGTON — The renewal of the USA Patriot Act is heading for final passage in the Senate after majority Republicans broke a two-month stalemate over the legislative centerpiece of President Bush’s war on terrorism.

The overwhelming Senate support for the two-bill package Wednesday virtually assured that Congress will renew the act before it expires March 10. The House was expected to pass the legislation Tuesday.

The law’s opponents, who insisted that new protections passed 95-4 Wednesday were cosmetic, conceded defeat.

“The die has now been cast,” acknowledged the law’s chief opponent, Sen. Russell Feingold, D-Wis., after the Senate voted 84-15 to end his filibuster. “Obviously at this point, final passage of the reauthorization bill is now assured.”

Senate passage holds great political value for Bush. Revelations late last year that he authorized a domestic wiretapping program raised concerns that his administration had granted law enforcement too much power in its bid to root out terrorists.

Every Senate Democrat and five Republicans refused to allow a vote on renewing the act before 16 provisions expired on Dec. 31.

Unable to break the deadlock, Congress opted instead to extend the deadline twice while negotiations continued. In the end, the White House and the Republicans crafted a second measure that would curb the power of law enforcement officials seeking information.

That was enough to win over all but a handful of Democrats.

Republicans have no intention of letting the victory go unnoticed this midterm election year.

After the House gives its blessing next week, Republicans are hoping to win a second day of coverage on Wednesday with a press conference by Speaker Dennis Hastert, R-Ill., and Senate Majority Leader Bill Frist, R-Tenn. The package will receive a made-for-television enrollment — usually a routine administrative procedure in which a bill approved in both houses is prepared for the president’s signature.

The House then will send the legislation to Bush, who will sign it before the deadline Friday.

The fanfare comes after the White House and GOP leaders finally broke the stalemate by crafting a second measure — in effect an amendment to the bill renewing the 16 provisions — that would somewhat limit the government’s power to compel information from people targeted in terror probes.

The second measure would add new protections to the 2001 antiterror law in three areas:

* Give recipients of court-approved subpoenas for information in terrorist investigations the right to challenge a requirement that they refrain from telling anyone.

* Eliminate a requirement that an individual provide the FBI with the name of a lawyer consulted about a National Security Letter, which is a demand for records issued by investigators.

* Clarify that most libraries are not subject to demands in those letters for information about suspected terrorists.

Feingold and his allies complained that the restrictions on government power would be virtually meaningless in practice. Though small, his group of four objectors represented progress for Feingold. In 2001, he cast the lone vote against the original Patriot Act, citing concerns over the new powers it granted the FBI.

On Wednesday, the package’s authors cast the vote in pragmatic terms.

“Both bills represent a vast improvement over current law,” said the author of the new curbs, Sen. John Sununu, R-N.H.

Feingold, a possible Democratic presidential candidate, said: “I am disappointed in this result. But I believe this fight has been worth making.”

With that, he began reading the Constitution and the Bill of Rights. Then he left the chamber. Feingold later returned to read resolutions from eight states expressing concerns about the Patriot Act.

“The debate is not yet closed,” Feingold said. “I believe there is still more that needs to be said.”