Four people were killed by mortar attacks in Baghdad and four more in bomb attacks that between them wounded 40, security officials said.
Roadside bombs wounded two in the capital and three near Tikrit, the hometown of the ousted dictator Saddam Hussein, officials said.
Other Iraqi cities across Iraq were hit by mortar attacks and bombs but there were no immediate reports of casualties.
Meanwhile, Iraqi President Jalal Talabani said after casting his ballot on Sunday that he had been asked by several blocs to continue in his post.
"I have been asked by many, many Iraqi groups and lists to re-candidate myself," he told reporters in English in the Kurdish city of Sulaimaniyah, 270 km north of Baghdad.
Talabani, wearing a suit and overcoat, walked with the aid of a cane into the polling station in one of the city's schools, escorted by around a dozen people.
In another development, anti-American Shiite cleric Moqtada Al-Sadr, speaking at a rare news conference in Tehran, has urged Iraqis to take part in election to help pave the way for Iraq's "liberation" from US forces.
Sadr's Mehdi Army, once a feared militia, has largely laid down its arms but his political movement is trying to make a comeback.
"Although holding elections under the shadow of occupation does not have legitimacy, I ask the Iraqi people to take part in the election as a political resistance move so that the ground is prepared for occupiers to leave Iraq," Sadr said on Saturday evening, Iran's official IRNA news agency reported.
"I ask the Iraqi people to go to the polls to elect the best people who can prepare the ground for Iraq's liberation," he said.
