Democrats are confident they have the votes to bring gun control legislation to the Senate floor this week. But getting the votes to pass the bill later this month will be much harder.

Senate Majority Leader Harry Reid (D-Nev.) has not yet conducted a formal whip count, but at least eight Republican senators have said they will not attempt to block an effort to bring up the measure, a senior Democratic aide said.

Fifty-five senators caucus with the Democrats, and Reid acknowledged he might lose a few votes on his side of the aisle. During his weekly press conference Tuesday, Reid declined to make any bold predictions. Asked if he had the votes, Reid responded, “I don’t know.”

Behind the scenes, Reid and his lieutenants are convinced they have the 60 votes necessary to start the debate on the floor.

“He’s always been confident that he can get 60 votes,” the aide said.