The most serious of the attacks on Tuesday was a blast that targeted a queue of soldiers and recruits at a Baghdad army base, killing 15.
"I came to Baghdad from Hilla with two friends to join the army," said one wounded recruit. "We were queuing with several other young people when there was an enormous explosion in the middle of the group."
An Iraqi interim interior ministry official said two soldiers and 13 volunteers were killed.
Elsewhere in the capital, unknown assailants ambushed the car of Mithal al-Alusi, a politician who favours normalising ties with Israel.
The politician survived, but two of his sons were killed together with a bodyguard.
"We were queuing with several other young people when there was an enormous explosion in the middle of the group"
A survivor of Tuesday's blast in Baghdad
"Yes, my two sons died and my bodyguard as well. It was a gunfire attack on my car near my house," al-Alusi said.
Fourteen other people were reported killed in the north and south of Baghdad.
Four Iraqis were killed by bombs in Salah al-Din province and armed group Ansar al-Sunna said in an internet statement that it had killed an Iraqi it accused of working for US forces.
The bodies of two other people who worked on US bases were found near Tikrit – ousted leader Saddam Hussein's hometown.
At Mosul, Iraq's third-largest city, two members of the Kurdistan Democratic Party were shot dead, while Iraqi soldiers killed two civilians who did not stop at a checkpoint near Baiji.
Croatia also said one of its truck drivers working in Iraq had been killed after his convoy carrying supplies for US troops was hit by a rocket.
Further south, two Iraqi men were shot dead apparently for voting in the elections and a woman council worker was seized in Mahmudiyah, police said.
The latest wave of violence come as four Egyptian engineers released 36 hours after they were seized, prepared to return home.
But there was no news about Italian journalist Giuliana Sgrena, who was seized in Baghdad on Friday.
Italian journalist Giuliana Sgrena
was abducted last week
An armed group that claims to be holding Sgrena has said in an internet statement that she would be freed "in the next few days".
France meanwhile said it was doing everything possible to secure the release of Florence Aubenas, a woman journalist abducted last month.
Aubenas and her translator have not been seen since leaving a Baghdad hotel on 5 January.
"We are doing all that we can, all that we should, in Baghdad and here, so that both of them get back home," French Foreign Minister Michel Barnier said.
Since Aubenas' disappearance, President Jacques Chirac has asked French journalists not to travel to Iraq.