WASHINGTON — Several Senate Republicans on Tuesday came out publicly against filibustering the first major gun control legislation since 1993 before it is even brought up for debate on the Senate floor, as advocates inched toward breaking a conservative blockade of the measure.
With backers of new gun safety laws increasingly optimistic that they can corral the 60 votes necessary to begin consideration of the measure, Sen. Harry Reid of Nevada, the majority leader, said he would schedule a showdown vote for Thursday. His comments came as lobbying on gun control stepped up on Capitol Hill, with the families of children killed in Newtown, Conn., four months ago fanning out across the Senate to personally appeal to lawmakers to vote ‘‘yes.’’
''We’re moving forward on this bill,’’ said Reid, who earlier Tuesday evoked his own father’s suicide by gunshot to implore consideration of the legislation, which would expand background checks for gun buyers, bolster school safety and crack down on people who purchase firearms for those who not entitled to own them. ‘‘The American people deserve a vote on this legislation.’’
Reid’s decision to move ahead came after Senate Republicans began splintering on whether the bill should be allowed full consideration on the Senate floor. Four Republican senators — Kelly Ayotte of New Hampshire, Susan Collins of Maine, Johnny Isakson of Georgia, and Tom Coburn of Oklahoma — said Tuesday that they would support a procedural motion to formally take up the gun legislation for debate and amendments. Other Republicans indicated that they were inclined to allow debate, joining Sens. John McCain of Arizona and Lindsey Graham of South Carolina.
''This is obviously an important issue,’’ Ayotte said. ‘‘We have a variety of views, and we should have an open vote.’’
Thirteen senators, led by a core of younger conservatives, had vowed to try to block any legislation that they saw as infringing on the constitutional right to bear arms.
Should Democrats secure the 60 votes they need, the Senate would then begin what is almost certain to be an emotionally volatile debate on the measure.
Advocates of a filibuster were not yielding, either to their colleagues, to President Barack Obama, who has been rallying support for a straight yes-or-no vote, or to the Newtown families making the same appeal.
‘'I took an oath to uphold the Constitution,’’ said Sen. Ron Johnson, R-Wis.