WASHINGTON — The House rejected a Thursday effort by Democrats to end the war in Iran and require President Donald Trump to get congressional authorization before proceeding.

But the vote on approving a war powers resolution was as tight as it could get: tied 212 to 212, which counts as a failed vote. And Democrats netted two more Republicans compared to the last time they forced a vote on a war powers measure in April — a sign of the GOP’s growing discomfort with Trump’s war without end.

Republican Reps. Thomas Massie (Ky.), Brian Fitzpatrick (Pa.) and Tom Barrett (Mich.) voted with Democrats in support of the resolution put forward by Rep. Josh Gottheimer (D-N.J.). Massie had previously supported putting parameters on the scope and duration of Trump’s military actions, but Fitzpatrick and Barrett had opposed these resolutions until now.

Thursday’s vote marks the third time this year Democrats have put Iran war powers resolutions on the House floor. In April, their resolution failed to pass by one vote.

“The dam is breaking,” said Rep. Gregory Meeks (D-N.Y.), the top Democrat on the House Foreign Affairs Committee. “Today’s tied vote signals that more Republicans are no longer willing to write this president a blank check for endless war.”