After two months of insisting that President Bush did not need court approval to authorize wiretapping of calls between the United States and suspected terrorists abroad, the administration is trying to channel the political pressure for more oversight into retroactive congressional approval for the program.
The administration opened negotiations with Congress last week, but it is far from clear whether Bush can get the votes he will need.
The latest Republican to join the growing chorus of those seeking oversight is Sen. Lindsey Graham of South Carolina.
In an interview yesterday on Fox News, Graham, a former military prosecutor whose opinion on national security matters commands respect in the Senate, said he believed there was now a "bipartisan consensus" to have broader congressional oversight of the program and judicial review.
"I do believe we can provide oversight in a meaningful way without compromising the program," he said, "and I am adamant that the courts have some role when it comes to warrants. If you're going to follow an American citizen around for an extended period of time believing they're collaborating with the enemy, at some point in time, you need to get some judicial review, because mistakes can be made."
Four other leading Senate Republicans, including the heads of three committees -- Judiciary, Homeland Security and Intelligence -- have said they would prefer some judicial oversight. Their positions, if they hold, could complicate the negotiations, which the White House is hoping will lead to legislation to approve the program retroactively, much as Congress eventually approved Abraham Lincoln's suspension of habeas corpus during the Civil War.
Bush expanded on his defense of the program in Tampa, Fla., on Friday, saying he believed that he had to take extraordinary steps in a time of war.
"Unfortunately, we're having this discussion," he said of the debate. "It's too bad, because guess who listens to the discussion: the enemy."
He added: "The enemy is adjusting. But I'm going to tell you something. I'm doing the right thing. Washington is a town that says, you didn't connect the dots, and then when you do connect the dots, they say you're wrong."
But two days before Bush spoke, the White House opened the door to talks in the hope of avoiding a full-scale congressional investigation. A series of senior officials, including Harriet E. Miers, the White House counsel, and Andrew H. Card Jr., the chief of staff, began contacting crucial members of the Senate to determine what it would take to derail the investigation.
The White House has refused to discuss those talks. Trent Duffy, a deputy press secretary, said the administration "does not want to negotiate in the media."
But some lawmakers have given glimpses of the conversations, including Sen. Olympia J. Snowe, a Maine Republican, a member of the intelligence panel who was prepared to vote with Democrats on Thursday to open an inquiry until the White House agreed to negotiate.
Snowe, who favors some kind of judicial review, characterized the talks as a "fundamental shift" in the debate. "I think there has been a quantum leap," she said in an interview, adding that senators were now "really trying to wrestle the best way to craft a measured bill."
The chairman of the Senate Intelligence Committee, Sen. Pat Roberts of Kansas, has said he would prefer to see the program brought under the authority of the court created by the Foreign Intelligence Surveillance Act. Roberts also says he is concerned that in an era of fast-paced electronic surveillance, the court may not be able to issue warrants quickly enough to meet the needs of the program.
Without offering specifics, Roberts talked of "streamlining FISA" and said the NSA would have to be involved in those negotiations.
Complicating the effort to reach a deal is the difficulty of surmounting the president's No. 1 objective: that no discussion make public the technology underlying the National Security Agency's spying effort.
The Senate Intelligence Committee has given the administration two weeks to negotiate. If the White House does not demonstrate a good-faith effort, members say, the Democratic proposal for a full-scale inquiry will be back on the table at the panel's next meeting March 7.
Republican leaders of the House Intelligence Committee have also agreed to some kind of inquiry related to the program, but there is a dispute about how broad it should be.
With Congress in recess for the next week, reaching an agreement on any legislation that contains concrete details seems unlikely.