The AUMF was written by Sen. Lindsey Graham, a vocal critic of the Obama administration's handling of Syria and ISIS, who said it is designed not to put limitations on where, when, or how the United States military pursues the group. That's in contrast, he argues, to the versions presented by the White House and Democrats on the Hill that restrict ground troops and sunset the authorization.
It is not clear when or if McConnell will schedule the measure for a debate and votes.
Almost all lawmakers say they want to pass an AUMF and argue it sends an important warning to the enemy as well as a reassuring signal of support to U.S. troops that would fight ISIS. But past efforts by Republicans and Democrats to approve one have broken down largely on partly lines about over the questions of whether and how to put restrictions on the use of force.
McConnell's move, which was largely unnoticed when he took it late Wednesday, was a surprise because McConnell indicated recently he didn't think a new AUMF was needed since the President is going after ISIS militarily based on a prior congressional authorization.
An aide to McConnell said the procedural step, known as Rule 14, was taken in case GOP leaders want to act but the aide said a decision hasn't been made whether to do that. The step bypasses the Senate Foreign Relations Committee, which is generally involved in writing AUMFs.
McConnell's actions were so subtle, Sen. John Cornyn of Texas, the number two Senate Republican, told reporters he didn't even know about them.
"I hope Sen. McConnell will bring the bill to the floor," said Graham. "I think it really is shameful we haven't had this debate in the Congress and I hope it will happen."
In a statement to CNN, McConnell spokesman Don Stewart said working through the Foreign Relations committee, chaired by Sen. Bob Corker, R-Tennessee, is the majority leader's preferred route.
"If the President decides to put forward a serious plan for defeating ISIL, and seeks an AUMF that doesn't tie the hands of this or any future Commander in Chief, this is the type of AUMF that would be effective and that the Leader would support," the statement said. "If the president moves in that direction and an AUMF is to be considered, it would be the intent of the Leader to consider an AUMF through the regular order, working with Chairman Corker and the Foreign Relations Committee."