Early results from Iran's presidential election have moderate candidate Hassan Rowhani with the lead. He has the support of reformists in Iran.
Rowhani has more than 53 percent of the 5.2 million votes counted early Saturday. Tehran Mayor Bagher Qalibaf had about 17 percent of the votes, and hardline top nuclear negotiator Saeed Jalili was in third place with about 13 percent.
It is not clear when the final results will be announced. About 50 million Iranians are eligible to vote, and Iranian media have reported turnout estimates of between 75 and 80 percent.
To win, a candidate must get more than 50 percent of the vote. If no one succeeds after the initial vote, a runoff election will be scheduled a week later.
Officials extended voting by several hours Friday to accommodate what they described as a large turnout in the country's presidential election.
Millions of Iranians voted to choose a successor to President Mahmoud Ahmadinejad, who is constitutionally barred from a third consecutive term.
Analysts say the high interest in the carefully orchestrated campaign may be due to the candidacy of moderate cleric Rowhani. Iran's former nuclear negotiator picked up the endorsements of leading reformists.
Former president Ali Akbar Hashemi Rafsanjani, another reformist leader who was barred from running by Iran's Guardian Council of clerics and jurists, had urged his supporters not to boycott the election.
Six candidates are bidding to replace current President Mahmoud Ahmadinejad. Most, including Jalili and Qalibaf, are considered hardliners who are loyal to the country's supreme leader, Ayatollah Ali Khamenei.
The supreme leader cast his vote in Tehran early Friday, telling U.S. officials who have been critical of the election, "the hell with you."
The election winner will be faced with an economy struggling with high unemployment and inflation, crippled by international sanctions imposed over Iran's disputed nuclear program.
While some candidates favor improved ties with the international community, major policy decisions rest with the supreme leader.