Early returns on Saturday night showed hard-line Iranian President Mahmoud Ahmadinejad's conservative opponents leading in elections for local councils and a powerful clerical body, widely considered a test of popular approval for the hardline leader.
Ahmadinejad's anti-Israel rhetoric and staunch stand on Iran's nuclear program are believed to have divided the conservatives who voted him into power. Some conservatives feel Ahmadinejad has spent too much time confronting the West and failed to deal with Iran's struggling economy.
Teheran newspapers and semiofficial news agencies reported unofficial results Saturday showing that no single party would be able to claim outright victory in Friday's elections, partly because of divisions within the conservative faction.
Iran's political scene is broadly split between conservative and pro-reform camps.
Officials have said preliminary results are expected Sunday, with final results coming Monday or later.