RAMADI, Iraq - Iraqis voted Wednesday in the first elections since the withdrawal of U.S. troops, braving extremists' bomb threats to polling stations as parts of the country remained engulfed in conflict.

The parliamentary elections come amid a deteriorating security situation, as a Sunni insurgency in the western province of Anbar against the Shiite-led central government pushes closer to the capital, Baghdad.

Cars were banned from streets across the country to deter violence as voting began at 7 a.m. In Anbar's provincial capital, Ramadi, intermittent explosions could be heard as polls opened. Turnout of Iraq's 22 million eligible voters was estimated at 60 percent.

Prime Minister Nouri al-Maliki, seeking a third term, is a front-runner. But no party is expected to secure a majority in parliament, meaning that the winner will have to build a coalition to form a government.

"Our victory is certain, but we are talking about how big is that certain success," Maliki said after voting in Baghdad.

"I call upon all the other groups to leave the past behind and start a new phase of good brotherly relations," he said.

Maliki's declining popularity may have been bolstered by his offensive in Anbar, where he has rallied Shiite support as the army fights hostile Sunni tribesmen and extremists from the Islamic State of Iraq and Syria, or ISIS. The group, inspired by al-Qaeda, has exerted control over parts of the province.

But in doing so, Maliki has taken a gamble. As deaths among security forces stack up, analysts say it is only a matter of time before the toll begins to erode his support. At least 172 Iraqi soldiers, police officers and armed allied tribesmen died in violence in April, according to an Agence France-Presse tally.

Authorities did not offer a timetable for releasing results, but they were expected to start trickling in to election officials in the coming days.

This article contains information from the Associated Press.