The brazen murders coincided with two co-ordinated car bombs in Najaf and Karbala — where a large Shia turnout is expected in the polls next month — that killed at least 58 people and wounded 100.

Five election commission workers were driving in Haifa Street in Baghdad, a stronghold of Sunni insurgents, when dozens of gunmen attacked their car with machineguns and grenades, dragging them out and setting the vehicle ablaze.

The insurgents shot one man in the head at point-blank range as one of his colleague knelt next to him before he, too, was murdered. The third man was shot in the head soon afterwards. Their bodies were left in the street as the gunmen paraded around an intersection close to the heavily protected International Zone. Two of the workers escaped.

“It’s not by killing employees that the elections are going to be hindered, but the terrorists have their own strategy,” said Farid Ayar, a spokesman for the electoral commission, which is employing thousands of Iraqis to work in polling centres and as election monitors.

In Najaf and Karbala hospitals were barely able to cope yesterday with the influx of dead and wounded. Witnesses in Karbala said that the bomber had been trying to hit a police recruitment centre, but found his way blocked and blew himself up in a bus station.

Najaf’s hospital could not deal with the bodies of 45 people killed during the funeral of a sheikh and witnesses reported seeing dogs scavenging body parts outside the clinic.

Officials say that such attacks underscore the need for elections. “Every day the people are dying, okay. If there are no elections, are they going to stop? No, so we have to make it,” Mr Arar said.

Iraqi and coalition officials are giving warning of a wave of violence in the build-up to the January 30 elections, which are opposed by hardline Sunni groups who fear that their traditional influence will be sharply eroded as the Shia majority gears up for the first time to vote en masse.

On Saturday, guerrillas fired mortar rounds at an election office near the troubled Sunni town of Samarra, to the north of Baghdad, killing two people and wounding six guards.

The start of the six-week election campaign has gone almost unnoticed in a capital traumatised by daily bombings, assassinations and criminal gangs. The only party to have organised a rally is the Communist Party, which last week drew 2,000 supporters to a hall at Baghdad’s main sports stadium. Armed guards frisked crowds of people waving red flags and singing campaign songs. Amid security fears, news of the meeting was spread only by word of mouth.

Many people are too scared to vote and confused about polling in a country where there used to be only one party and one candidate. Now there are almost 8,000 candidates and 130 political organisations cautiously building coalitions in a system where no one knows how the people will vote, or even if they will turn out.

The parties have coalesced into more than 100 lists, which will field candidates for the 275-seat parliament. The assembly will serve for one year, during which it will draw up a constitution for fresh elections without the influence of the American occupation. The choice for a people long starved of democracy is dizzying: the Assembly for the Grandchildren of the Twentieth Revolution, the Niche Martyr Foundation for Islamic Notification and the Movement of Farmers and Oppressed Peoples of Kurdistan feature among more mainstream parties. Even the bighitters have spawned sub-groups and splinters — the armed wing of the leading Shia party, the Supreme Council for the Islamic Revolution in Iraq, is running on its own ticket.

Western diplomats admit that they have trouble identifying all the parties and say that it is impossible to predict which groups the Iraqis may back.

One of the leading lists is the Unified Iraqi Alliance, a gathering of mainstream Shia candidates that was drawn together — if not explicitly backed — by Grand Ayatollah Ali al-Sistani, Iraq’s most influential cleric. The list receives support from many Shia imams at Friday prayer meetings, although whether moderate Shias will be put off by the clerical influence is unknown.

Other groups are less canny in getting their message across. Asked by The Times about his manifesto, the leader of one small group, The Justice and Democratic Advancement Party, refused to divulge any information. “There are some people who want to steal our programme and I can’t give this to anybody,” he said.

The interim Government and its American backers hope that the elections will confer a new legitimacy on the Iraqi leadership, but observers fear that a Sunni boycott could reinforce the raging insurgency and terrorist campaigns.

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