The U.S. Senate rejected a motion to advance a joint resolution on Iran war powers Wednesday with a 49-50 vote, marking the narrowest margin yet on the issue and coming with a new Republican defection. Senator Lisa Murkowski of Alaska voted yes on the discharge motion after opposing prior versions of the measure, joining Senators Rand Paul of Kentucky and Susan Collins of Maine as the only Republicans siding with the Democratic majority on S.J.Res. 163, which would have directed the removal of U.S. Armed Forces from hostilities in or against Iran not authorized by Congress.

The motion still fell one vote short, with Senator Pete Ricketts of Nebraska listed as not voting and Senator John Fetterman of Pennsylvania serving as the sole Democrat to cast a no vote. Murkowski stated she had opposed every prior resolution because she believed an abrupt withdrawal would endanger American forces, noting her shift came after the 60-day War Powers window passed without the administration providing clarity on the legal basis for continued operations.

The roll call, recorded as Vote Number 118 at 11:29 a.m. on May 13, 2026, listed the question as a motion to discharge S.J.Res. 163—a joint resolution directing the president to remove U.S. forces from Iran hostilities unless Congress explicitly authorized the action through a declaration of war or specific military force authorization. The vote was rejected 49-50 with one senator abstaining.

Three Republicans voted yea: Murkowski, Collins and Paul. Fetterman remained the lone Democrat voting no while Ricketts did not vote. The resolution, led by Senator Jeff Merkley of Oregon, required the president to withdraw forces from Iran hostilities unless Congress explicitly authorized the action. The White House argued the War Powers clock stopped running on April 7 following a ceasefire, but Murkowski and others pushed back, citing ongoing military posture that maintained constitutional authority questions. Defense Secretary Pete Hegseth told Murkowski the administration retains necessary Article II authority if strikes resumed, though she countered deployed troops and warships made hostilities appear incomplete.

The procedural contest centers on the 1973 War Powers Resolution, which requires presidential reporting after force deployment without a declaration of war and limits unauthorized engagement to 60 days. The administration maintained active hostilities terminated with the April 7 ceasefire, but senators argued Congress still holds constitutional authority given persistent military positioning. Murkowski’s shift followed the expiration of the 60-day window and insufficient administrative clarity, underscoring growing pressure on the White House to address congressional concerns ahead of potential escalations in Iran-related operations.