Maine Republican U.S. Senator Susan Collins broke with her party leadership Thursday to vote for a war powers resolution to halt military actions against Iran.

Collins has signaled since last week that she would vote to end the war when a 60 day threshold requiring congressional approval arrived, which is Friday.

She joined GOP Kentucky Senator Rand Paul to back the measure, which was still rejected by the Republican majority.

The vote was 47-50, with Democrat John Fetterman joining Republicans.

Collins says she won’t support further military action without a “clear mission” and a “defined strategy” for bring the conflict to an end.

“Our military has performed magnificently and with great courage and sacrifice in diminishing the threat that Iran poses to our country, our allies, the broader Middle East, and the world,” she said in a statement.

“Further military action against Iran must have a clear mission, achievable goals, and a defined strategy for bringing the conflict to a close. I voted to end the continuation of these military hostilities at this time until such a case is made,” she said.

Collins faces a competitive and closely watched reelection battle this year, with Democrats hoping to flip her seat in November.