The vote came as a growing number of Republicans have broken from President Trump on the conflict, reflecting voters’ concerns ahead of midterm elections.

© Arash Khamooshi/Polaris for The New York Times

In a federal lawsuit filed on Thursday, an advocacy group asked a federal judge to declare that the seven-month war in Iran was never declared or authorized by Congress.

© Tierney L. Cross/The New York Times

The dissent reflects growing unease about the party’s prospects in November, as the G.O.P. struggles to overcome the president’s unpopularity.

© Kenny Holston/The New York Times