The Senate is set to begin debate Monday on a bill that would overhaul the rules for electronic surveillance, but the measure faces major hurdles.

Majority Leader Harry Reid, D-Nev., filed for cloture Dec. 14 on a motion to proceed to the bill (S 2248), and Democrats expect to win the 60 votes needed to move to debate.

But Democrats face a daunting challenge in enacting legislation that achieves their goal of scaling back broad administration surveillance powers granted by a temporary law that expires in February (PL 110-55). They must act quickly or they will be forced to choose either to extend the law or to let it lapse and endure Republican criticism that they are leaving the country vulnerable to potential terrorist attacks.

The measure, which the Senate Intelligence Committee approved, would permit ­warrantless surveillance that targets foreigners overseas, even if they are communicating with someone in the United States. But the measure would give the secret court created by the Foreign Intelligence Surveillance Act, or FISA (PL 95-511), the power to approve several aspects of how the surveillance is conducted. The temporary law has fewer court checks.

The bill also would grant retroactive legal immunity to telecommunications companies alleged to have participated in the National Security Agency’s warrantless surveillance program.

A competing substitute amendment, passed by the Senate Judiciary Committee, would place additional conditions on how surveillance is conducted and would not grant the legal immunity.

Although staff aides for both committees have been working to incorporate some of the Judiciary amendment’s spying provisions into the Intelligence bill, the differences over immunity have been too steep to overcome in negotiations. So the Judiciary amendment to the bill will automatically be the pending amendment to the Intelligence bill.

That means the Senate could vote at least once on language that would not grant immunity, although such votes are likely to fail because the White House, Senate Republicans and many Democrats support immunity.

A number of other amendments in the works also would address the issue, but as of Dec. 14, no agreement had been reached to finalize the amendment process. A second cloture vote probably will be necessary to move toward passage of the bill, given a filibuster threat led by Christopher J. Dodd of Connecticut, a Democratic presidential candidate.

Reid announced the complex floor procedures after consulting with Senate Intelligence Chairman, John D. Rockefeller IV, D-W.Va., and Judiciary Chairman Patrick J. Leahy, D-Vt.

Reid said he opposed retroactive legal immunity and tried to push a separate bill that would not grant it (S 2440). “But I cannot ignore the fact that the Intelligence bill was reported favorably by a vote of 13-2, with most Democrats on the committee supporting that approach,” he said.

“Our ultimate goal is a bill that commands broad bipartisan support in the Congress and in the country,” Reid said. “The process I just outlined offers us the best opportunity to do so.”

On Sunday, Reid sent a letter to Director of National Intelligence Michael McConnell, requesting that he provide the full Senate with administration documents related to the immunity question that have been provided to the Intelligence and Judiciary committees.

“In my view, each sitting senator has a constitutional right of access to these documents before voting on this matter,” Reid wrote.

Although the topic of immunity has consumed much of the informal debate over the legislation so far, numerous differences remain between the Intelligence and Judiciary versions of the bill.

A Senate aide said the two panels have been trying to work out agreement on warrant requirements for spying on U.S. citizens overseas. Aides said all the negotiating parties support the requirements in principle, but have been trying to reach an agreement on technical points.

Another point of discussion between the panels is the bill’s expiration date. The Intelligence bill would sunset in six years, and the Judiciary bill would do so in four years. Most Democrats prefer the four-year sunset, but Republicans and the White House want no sunset date at all.

A third subject of negotiations, which were expected to continue into the weekend, is over so-called exclusivity language. The two bills have different takes on the extent to which FISA should be the “exclusive” law governing electronic surveillance.

Senators have been in contact with the Office of the Director of National Intelligence and the Justice Department during the negotiations.

One aide familiar with the discussions said that if an agreement could be reached on those points and others, a manager’s amendment or series of manager’s amendments would be offered by any combination of Rockefeller, Leahy, ranking Intelligence Republican Christopher S. Bond of Missouri and ranking Judiciary Republican Arlen Specter of Pennsylvania.

Republican Jon Kyl of Arizona has raised objections to the language that would require warrants to target U.S. citizens overseas in terrorism-related investigations, arguing that as constructed it would be easier to listen in on such calls in routine criminal investigations. Kyl said Dec. 14 he would consider offering an amendment to change the language “depending on how it comes to the floor.”

Other expected amendments are related to lawsuits filed against telecommunications companies alleging they violated privacy rights by participating in the NSA’s warrantless surveillance program.

Dodd and Russ Feingold, D-Wis., plan to offer an amendment that would strip the immunity language entirely.

Charles E. Schumer, D-N.Y., has readied an amendment to ensure that plaintiffs have legal standing to sue, since they’ve had difficulty proving that they’ve been subject to surveillance.

Dianne Feinstein, D-Calif., has an amendment based on an earlier proposal, by Sheldon Whitehouse, D-R.I., that would require the FISA judges, meeting together, to determine that telecommunications companies acted in good faith before they received immunity. Under the Intelligence Committee’s version of the bill, immunity would be granted if the attorney general certified that the companies had acted pursuant to an official request for authorized surveillance.

Specter, Whitehouse and others have signaled that they intend to offer an amendment that would substitute the government, instead of the companies, as the defendant in the lawsuits.

Rockefeller said he was confident that his bill would win the 60 votes it needs to pass, a prediction echoed by many Democratic and Republican aides.

But one Senate GOP aide questioned whether there were enough votes to achieve cloture on the motion to proceed.

Even if the bill does pass the Senate, the House has passed legislation (HR 3773) that would not grant immunity, setting the stage for a difficult conference to reconcile differences between the measures.

First posted Dec. 14, 2007 8:58 p.m.