Senate advances vote to force Trump to end Iran strikes

The Senate moved closer to forcing President Donald Trump to end U.S. military action in Iran, with Democrats winning a 50-47 procedural vote that drew four Republican backers and exposed a rare rebellion inside Trump’s party.

Susan Collins of Maine, Lisa Murkowski of Alaska, Rand Paul of Kentucky and Bill Cassidy of Louisiana joined most Democrats to advance the resolution. John Fetterman of Pennsylvania was the lone Democrat to vote no. The vote was the strongest showing yet for a war powers challenge that had been blocked repeatedly since the conflict began in late February 2026.

The measure would require Trump to stop hostilities in Iran unless Congress authorizes the war, invoking the 1973 War Powers Resolution. Democrats argued that the law’s 60-day clock had already expired on May 1, 2026, giving Congress a constitutional basis to reclaim authority over an operation launched without explicit approval. That argument sits at the center of the fight on Capitol Hill: whether the White House can keep prosecuting the conflict on its own, or whether lawmakers will force a new vote before U.S. forces remain engaged.

Cassidy’s support carried special weight. It was the first time he had backed advancing a war powers resolution, and it came days after he lost enough support in the Louisiana GOP Senate primary to avoid a runoff. Trump had endorsed one of Cassidy’s opponents, making the senator’s break with the White House even more striking. The Louisiana Republican became the fourth GOP senator to vote to advance the measure, a small bloc but one large enough to push Democrats over the procedural threshold.

The vote also marked a clear escalation from last week, when the same effort failed 50-49 on May 13, the closest margin so far. Murkowski first backed the measure in that earlier vote, alongside Collins and Paul, and the new tally showed Democrats had finally added enough cross-party support to keep the resolution alive.

Even so, the fight is far from over. The Senate’s vote advanced the measure, but it still faces additional hurdles before it could take effect, leaving Trump’s Iran policy intact for now. Still, the result gave Democrats a symbolic breakthrough and a notable sign that even a narrow Republican defection can put real pressure on the White House when Congress asserts its war powers.