Spurred in part by President Bush, congressional negotiators said last night that there is at least a 50-50 chance they will reach agreement on a bill to revamp the nation's intelligence community in time for it to be enacted this month.

Sen. Joseph I. Lieberman (D-Conn.), a key negotiator, said senators have had to make several concessions to the House regarding powers of the proposed national intelligence director. But they are justified, he said, in the name of reaching a compromise.

"I think we're going to end up where very few people will be thrilled," Lieberman said in an interview. But the goal, he said, is to find an agreement that the House and Senate will approve -- presumably by this weekend -- and that the president will sign. "I'm encouraged," he said, adding that it is still possible the effort could crumble.

Bob Stevenson, spokesman for Senate Majority Leader Bill Frist (R-Tenn.), noted that hopes for the House-Senate negotiations have waxed and waned in recent weeks. Last night, he said, "it's as close as it has been."

Working with recommendations issued this summer by the Sept. 11 commission, the House and Senate passed wide-ranging bills that were similar in some general areas and different in hundreds of specifics. House-Senate conferees have tried for weeks to resolve the differences.

Bush, who was criticized by some commission members and by others for taking a largely hands-off posture, telephoned House Armed Services Committee Chairman Duncan Hunter (R-Calif.) last weekend to urge him and other negotiators to find a consensus.

Hunter is a strong advocate of the Defense Department, which has resisted the Senate's call for it to surrender some of its control over intelligence agencies such as the National Security Agency. The new intelligence director needs substantial control over such agencies to coordinate the nation's anti-terror efforts, senators say.

The House and Senate bills would create the national intelligence director and a counterterrorism center, but they differ on the powers each would have. Lieberman, interviewed during an evening break in the closed-door negotiations, said senators have had to yield ground in areas such as the intelligence director's budgetary authority.

The Senate bill originally called for the director to "determine" the government's total intelligence budget and to "manage and oversee" how the funds are distributed. The House bill would grant less clout, allowing the director to "develop" the intelligence budget and ensure its "effective execution."

House conferees agreed earlier to the Senate language allowing the director to "determine" the budget. But they have been less yielding on questions of managing the actual spending.

Lieberman said last night, "We fought very hard for our bill on budget authority, but we couldn't get everything we wanted."

He declined to offer specifics, noting that negotiations were still underway.

Even with the Senate's concessions, he said, the budget authorities a national intelligence director would wield "are clearly better than the status quo." In the end, he said, the new director will have "very strong powers on shaping the budget, and strong powers on spending it, too."

Lieberman said negotiators also were trying to resolve matters involving immigration, law enforcement and protecting Americans' civil liberties while waging a war against terrorism.