Public support for the war in Iran has fallen to its lowest level since the conflict began five months ago, with only one in three Americans backing the military campaign, according to a new Reuters/Ipsos poll.

The survey found growing skepticism over President Donald Trump's handling of the conflict, with 69% of respondents — including four in 10 Republicans — saying he has not clearly explained the goals of U.S. military involvement in Iran.

Trump has offered varying reasons for the war, including preventing Iran from obtaining a nuclear weapon, weakening its missile program and encouraging regime change.

White House spokeswoman Olivia Wales dismissed the poll, saying Trump would not base national security decisions on "fluid opinion polls" and insisting his priority is preventing Iran from acquiring a nuclear weapon.

While Trump's overall job approval ticked up three points to 37%, support for the war has remained below 40% throughout the conflict, far below the early backing seen for the wars in Iraq and Afghanistan.

The declining support presents a political challenge for Trump and congressional Republicans as they head into the November midterm elections.

"It's not clear why we started a war with them. I have no idea," said Alex Womack, a retired Georgia turbine repair specialist and Republican who said the conflict has weakened his support for Trump.

The war has killed 18 U.S. service members, while thousands have died in Iran and Lebanon. Americans have also felt the conflict through higher fuel costs, with the national average price for gasoline rising to more than $4 a gallon from about $3 before the fighting began.

Republican strategist Alex Conant said the war has complicated the GOP's political message.

"This puts pressure on the party in a myriad of ways, all of them bad," Conant said, arguing the administration is struggling to focus on economic issues while the conflict dominates the agenda.

The poll also found independent voters currently favor Democratic congressional candidates over Republicans by 36% to 20%, while giving Democrats the edge on economic issues.

During the 2024 campaign, Trump pledged to avoid long wars and predicted the Iran conflict would end within weeks. Instead, the fighting has stretched into its fifth month.

"I know we have allies and things like that, but there's a lot of people here that really need help," said Rhyan Anderson, a Georgia independent who voted for Trump in 2024.

The Reuters/Ipsos online poll surveyed 1,246 U.S. adults from Friday through Sunday and has a margin of error of plus or minus 3 percentage points.