The Senate on Wednesday rejected another Democratic attempt to limit President Trump's military authority against Iran, but growing Republican opposition to the conflict was evident as the measure failed by a single vote, 49-50.

Republican Sen. Lisa Murkowski of Alaska voted against the war for the first time since the conflict began in late February, joining GOP Sens. Susan Collins of Maine and Rand Paul of Kentucky in opposing the military action. Sen. John Fetterman of Pennsylvania was the only Democrat to vote against the war powers resolution.

The vote marked the seventh attempt by Democrats to force congressional oversight of the Iran conflict through war powers legislation. Democratic Sen. Tim Kaine of Virginia, who has led the effort, said before the vote that he believes the Senate will eventually tell the president to "stop this war."

The Trump administration maintains it does not need congressional authorization for the military campaign, arguing that hostilities have been "terminated" due to a ceasefire arrangement. Defense Secretary Pete Hegseth told lawmakers this week that the administration believes it has "all the authorities necessary" to resume attacks on Iran without seeking congressional approval.

Republican leadership continues to support the military action, with Sen. John Barrasso arguing that the conflict has put Iran's economy "on life support" and eliminated its leadership. However, some GOP senators have expressed concerns about rising gas prices as elections approach and have called for dialogue between the executive and legislative branches on constitutional war powers.

Even if a war powers resolution were to pass the Senate, it would face uncertain prospects in the House and would likely be vetoed by Trump. Democrats say the repeated votes are aimed at building political pressure on the president to either withdraw from the conflict or seek proper congressional authorization.