The attacks struck civilian, government and security targets. There was no immediate claim of responsibility for any of the blasts, which were spread out in more than half a dozen provinces in Iraq. At least one of the devices in a southern region was dismantled before it blew up.

The extent to which any of the attacks were coordinated was not clear, but they were some of the most widespread in recent weeks, striking a variety of targets that brought to the forefront Iraq's political and ethnic diversity. The last similar daily toll was on Nov. 6, when a bomb killed more than two dozen people at a military base in Taji.

Violence in Iraq is less frequent than at the height of the insurgency, although militias have often struck at the country's security forces to undermine confidence in the government's ability to keep order.

On Wednesday, some of the worst violence was in the north. In the city of Kirkuk, 9 people were killed and 31 wounded by three car bombs targeting the headquarters of Kurdish and Turkmen political parties. At the southern entrance to the province, the governor, Omar al-Humairi, escaped an assassination attempt in which a roadside bomb targeted his convoy, and a car bomb blew up inside a parking lot in the west of the city, wounding one person.

In Mosul, a city in the north, a bomb exploded as an Iraqi Army patrol passed, wounding five service members and two civilians. Two improvised explosive devices were in front of Mosul University's College of Science and the College of Engineering, but neither caused casualties.

In Salahuddin Province, also in the north, an improvised explosive device detonated in the city of Baiji, wounding four members of the security forces.

In Diyala Province, 13 civilians were wounded in three separate attacks: a car bomb, an improvised bomb and another explosive device.

In the capital, Baghdad, a car bomb targeting the convoy of a high-ranking officer in charge of protecting a ministry exploded near the Ishtar Sheraton Hotel, killing a civilian and wounding six people living in, working in or visiting the neighborhood.

South of the capital, a car bomb exploded inside a busy market in Hilla, killing 7 people and wounding 33, while a device planted near a primary school for girls wounded 11 students.

Local officials in many parts of Iraq have often complained that security leaders are corrupt or have no strategy to protect civilians by pre-empting militia strikes. On Wednesday, after the attack in Hilla, a provincial government security adviser, Hassan al-Janabi, said in a telephone interview that there should be a change of leadership in the forces in Babil Province because of "repeated security breaches."

In Kut, also south of Baghdad, 3 civilians were killed and 15 wounded when a bomb in a parked car exploded.

In the area of the holy Shiite city of Najaf in the south, security forces defused a car bomb, a commander, Lt. Gen. Othman Ghanimi, said in a statement.

Yasir Ghazi reported from Baghdad, and Christine Hauser from New York. Employees of The New York Times contributed reporting from the Iraqi cities of Kirkuk, Babil and Mosul.