Graham intends to offer as an amendment competing legislation that would change the background check system, but not expand it.
Advocates are frantically lobbying a small and rapidly shrinking list of undecided senators from both parties who control the fate of the most ambitious gun control legislation to reach the floor in nearly 20 years.
Senate leaders spent Monday quietly working to set up a vote later this week on the proposal, which would require background checks for all private firearms sales over the Internet and at gun shows. Current law requires background checks only for commercial gun sales made through licensed dealers.
In the meantime, the spotlight swung to the handful of senators who are still evaluating whether to vote for or against the measure, cosponsored by West Virginia Democrat Joe Manchin III and Pennsylvania Republican Patrick J. Toomey. The measure will be voted on as the first amendment to broader legislation (S 649) that also would create new criminal penalties for gun traffickers and authorize $40 million a year for school security improvements.
Every senatorís vote will be critical as gun control supporters hope to push the proposal over the 60-vote threshold likely to be required. The measure appeared to have the public support Monday of at least 52 senators, including 49 Democrats and independents and three Republicans: Toomey, Susan Collins of Maine and Mark S. Kirk of Illinois.
One Democrat who had been a holdout, Jon Tester of Montana, said Monday night he had read the amendment and would support it.
But the task of finding an additional eight senators to support the plan appeared to grow more daunting for gun control supporters Monday. Several previously undecided Republicans ó including Bob Corker of Tennessee, Lindsey Graham of South Carolina, John Hoeven of North Dakota and Johnny Isakson of Georgia ó announced Monday that they either oppose the amendment or are very likely to oppose it.
Senate Majority Leader Harry Reid, D-Nev., signaled that Democrats are still rounding up votes as he declined to file cloture on the amendment and instead said he was negotiating with Republicans to come to a mutual agreement. Democratic leaders initially hoped to vote on the Manchin-Toomey plan Tuesday.