Sen. Thom Tillis (R-NC) joined Democrats and a handful of Republicans in voting on Thursday for a war powers resolution demanding an end to the war in Iran. But, despite growing calls from vulnerable Republicans ahead of the midterm elections, most of the GOP continued to vote against the war powers effort, and the measure failed by a 50-49 vote.

“We’re reaching a point to where we just need answers. We got to know what success looks like,” Tillis, who is not running for a third Senate term, said earlier this week. “There’s never been any way to measure what success looks like. … For every step we take forward, we take a step back.”

He also highlighted the economic costs of the war, opposition from voters and concerns that the war could drag on indefinitely.

Sens. Susan Collins (R-ME), Lisa Murkowski (R-AK) and Rand Paul (R-KY) also voted for the resolution, while Sen. John Fetterman (D-PA) voted against it.