Senators labored for consensus Thursday on a bill that would change part of the USA Patriot Act that allows the Bush administration to fire and replace federal prosecutors indefinitely without Senate confirmation. But a floor vote seemed unlikely this week.

Freshly briefed by the Justice Department on the forced resignations of some of the seven U.S. attorneys affected, Senate Democrats planned to bring a bill to the floor that would impose a 120-day deadline on the amount of time a replacement could serve without confirmation.

After that, an interim replacement would be named by a U.S. District Court. Attorney General Alberto Gonzales and some Republicans say that could lead to the appointments of prosecutors for reasons other than their qualifications. Senate Republicans and Democratic leaders were trying to strike a compromise that might lengthen the 120-day period or curb the appointment power of the District Court.

But Democrats want to give the Justice Department motivation to move swiftly toward Senate confirmation of federal prosecutors, saying the Patriot Act now opens the way for an attorney general to install political allies indefinitely.

It's the latest effort by majority Democrats to curb what they say is the Bush administration's virtually unchecked power during six years of GOP congressional contol — even though the Patriot Act reauthorization that contains the provision at issue was passed last year overwhelmingly, with bipartisan support. Lawmakers of both parties, including the Republican author of the law, say they were unaware of the way the Justice Department might use that rule.

Gonzales, meanwhile, has said that he intends to submit the name of every newly installed prosecutor to the Senate for confirmation.

The issue was inspired by the recent firings of seven U.S. attorneys, some without cause, Deputy Attorney General Paul J. McNulty told the Senate Judiciary Committee. Democrats contend that prosecutors were forced to resign to make way for Republican political allies, and that the White House slipped the provision into the Patriot Act to permit such indefinite appointments.

Congress passed the reauthorization with overwhelming bipartisan support, but many lawmakers say they were unaware of the provision. The president appoints federal prosecutors, who are subject to Senate confirmation.

Gonzales has said he intends to submit every newly appointed interim prosecutor to the Senate confirmation process and denied that his choices were politically motivated. He also has pointed out that U.S. attorneys serve at the president's pleasure and can be fired for any reason or no reason at all.

Nonetheless, Senate Majority Leader Harry Reid of Nevada is expected to try to bring the bill up for a vote Thursday, which also is the last day on the job of one of the fired prosecutors, Carol Lam of San Diego.

Sen. Jon Kyl, R-Ariz., said last week he would try to block the bill unless Reid agreed to strip out the appointment power of the U.S. District Court.

McNulty briefed senators behind closed doors Wednesday night on the cases of the seven fired prosecutors. Attending the meeting were Republicans Kyl and Arlen Specter of Pennsylvania and Democrats Chuck Schumer of New York, Dianne Feinstein of California and Patty Murray of Washington.

Afterward, Murray said she heard nothing to suggest that the U.S. attorney in her state, John McKay, deserved to be fired. She and other participants refused to comment further.

Earlier this month, McNulty told the committee that most of the seven had been fired for "performance-related" reasons, and that one in Arkansas, Bud Cummins, had been cleared out to make way for a former aide to White House adviser Karl Rove.

However, McKay and others had received glowing performance reviews and were not told of performance issues before they were fired, prompting further investigation by the committee.