After weeks of negotiations and closed door meetings, moderate Republicans on the Senate Intelligence Committee will propose legislation giving President Bush's controversial surveillance program the force of law.

Support was building Tuesday among Republicans and the White House for the proposal to craft eavesdropping legislation and conduct additional oversight more than four years after Bush secretly initiated the program. The move also blunted Democratic calls for an investigation of the U.S.-based monitoring operations in the Senate Intelligence Committee.

Committee Chairman Pat Roberts, R-Kan., said the legislation proposed by several moderate Republicans was "certainly a good foundation to start with" — a sentiment shared by the Senate's Republican leadership and the White House, he said.

Sen. Mike DeWine, R-Ohio, said he would soon introduce the Terrorist Surveillance Act of 2006 with three other moderates who have helped shaped the debate on intelligence issues: Sens. Chuck Hagel of Nebraska, Olympia Snowe of Maine and Lindsey Graham of South Carolina.

Roberts said he believed that Bush would sign surveillance legislation after "Congress worked its will." But he said there may still be changes ahead on the proposal now under consideration. "I don't see every 't' crossed and 'i' dotted," Roberts said.

It's also unclear if the House will consider a similar measure. House Intelligence Chairman Peter Hoekstra, R-Mich., has not yet taken up legislation.

Meanwhile, Democrats on the Intelligence Committee expressed outrage after a meeting Tuesday that senators voted — along party lines — to reject an investigation of the surveillance proposed by West Virginia Sen. Jay Rockefeller, the committee's top Democrat.

"The committee — to put it bluntly — basically is in the control of the White House," a visibly angry Rockefeller said.

Roberts balked at Rockefeller's suggestion. Roberts told reporters that he asked the committee to reject confrontation and accommodate an agreement with the White House to create a subcommittee of seven senators with broad oversight of the National Security Agency's terrorist monitoring.

"We should fight the enemy. We should not fight each other," Roberts said.

The 15-member panel agreed, over strong Democratic objections that the limited size of the group means Congress will be writing laws in the dark. "Our committee has to be fully informed if we are to guide the legislative debate on this program that is fast approaching," Rockefeller said.

The growing call for legislation has added pressure on the Bush administration to go along, and the White House indicated a broad approval for DeWine's bill.

"We think it is a generally sound measure," White House spokeswoman Dana Perino said. "We have said we are committed to working with Congress on legislation that would further codify into law the president's authority to detect and prevent potential attacks."

Yet even as legislation is drafted, lawmakers are pressing for more details about the surveillance.

Rockefeller said he spent all of Friday at the NSA, seeking answers to more than 400 questions. He said it would take several visits to have a full understanding of the program, which allowed the administration to eavesdrop on international calls and e-mails of U.S. residents when terrorism is suspected.

Senate Judiciary Committee Chairman Arlen Specter, R-Pa., also threatened to write legislation to limit funding for the program if he can't get more information about it. "If we cannot find some political solution to the disagreement with the executive branch, our ultimate power is the power of the purse," Specter said.

Rivaling the DeWine approach, Specter is writing a separate bill that would allow the secretive Foreign Intelligence Surveillance Court the authority to give the program a broad constitutional blessing every 45 days. Specter's support remains unclear.

DeWine's bill would — for a time — exempt the president's surveillance program from a 1978 law aimed at governing electronic intelligence collection inside the United States.

The proposal, now being circulated on Capitol Hill, would allow the government to monitor suspected terrorists for up to 45 days without first seeking approval from the federal intelligence court. The government would then have three options: stop the surveillance, seek a warrant from the court, or come to Congress to explain why a warrant isn't possible.

DeWine said his approach would create a subcommittee to consider those requests and conduct in-depth oversight of the monitoring on a case-by-case basis.

Like the president's program, his bill covers only communications where one party is overseas and one is inside the United States.

The White House has said that Bush acted lawfully when he ordered the warrantless surveillance because he had the inherent authority as president and under a September 2001 resolution to use force in the war on terror. Although initially reluctant to work with Congress on a bill, the White House has come around in recent weeks as lawmakers threatened investigations.

Roberts and Senate Majority Leader Bill Frist, R-Tenn., both indicated their support for the concept drafted by the moderate senators. But in a sign of how carefully lawmakers must handle the debate, Frist sought to make clear the president's actions are legal now, noting that he believes Bush already "has the constitutional authority to conduct this program."