ABUJA (Reuters) - Nigeria postponed parliamentary elections until Monday after voting materials failed to arrive in many areas, a major blow to hopes of a break with a history of chaotic polls in Africa's most populous nation.
Voters had trooped early to polling stations across the country of 150 million, eager for a ballot less tainted by fraud and violence than 2007 elections that lacked credibility in the eyes of Nigerians and international observers.
The postponement brought bitter disappointment.
"Nigeria has not changed and today we have seen that," said Kingsley Eze, 23, an amateur jazz musician in Port Harcourt, hub of the oil industry which provides most of Nigeria's exports.
Confusion added to the frustration in Nigeria's biggest cities -- the commercial capital Lagos in the south and Kano in the north -- where voting went ahead in some places because election materials had arrived on time.
"It only tells how grossly incompetent we are about nearly everything," complained computer engineer Bayo Ayodele in Lagos.
"I bet you most people who were disappointed will not come back on Monday... After all, our votes don't usually count."
President Goodluck Jonathan, favourite to win re-election on April 9, was among those to discover that voting materials had not reached his home region, in the oil-producing Niger Delta. It was the same across much of Nigeria.
"If we must do something, it is better to delay it and do it well," Jonathan said, urging Nigerians to show understanding and expressing confidence the country was capable of credible polls.
The parliamentary polls had been seen as a litmus test ahead of the presidential election in a week's time and governorship votes in the 36 states a week after that.
The delay raised questions about what would happen to those votes that had been cast. Voters argued with police officers at one polling station in Lagos over what to do, as a policeman clutching a full ballot box sped past on a motorcycle taxi.
"Our initial reaction is that we suspect there is a deliberate attempt to sabotage the elections and undermine the electoral commission," said Yinka Odumakin, spokesman for ex-military ruler Muhammadu Buhari, Jonathan's main rival.
Successful elections would be another fillip for foreign investment in Nigeria and across fast-growing Africa as well as strengthening Nigeria's international clout.
But failure could raise questions about how well-entrenched democracy is, more than a decade after the end of military rule.
"The questions now are how badly shaken is confidence in the electoral process, and will the already-deployed election materials be held securely," said one Western diplomat.
The head of the Independent National Electoral Commission (INEC) blamed the delay on the failure of a supplier to get materials shipped on time.
"The decision we have taken is weighty indeed but it is an important step in further ensuring the credibility of the 2011 elections," Attahiru Jega said in a televised address, adding that he was confident all would be in place on Monday.
Jega, credited with electoral reforms designed to prevent cheating, made no suggesting of delaying the other ballots.
"Professor Jega was given almost $1 billion to run this election and he can't even get ballot papers printed on time. He has created a national fiasco of monumental significance," said Roland Ewubare of the National Human Rights Commission.
Observers from the Commonwealth appealed to Nigerians to remain calm so an orderly vote could still take place.
Little violence had been reported on Saturday beyond parts of the volatile Niger Delta, where several people were reported killed in a shooting in Bayelsa state and a member of parliament was kidnapped at gunpoint in Rivers state.
In the election run-up, there had been isolated bomb attacks on campaign rallies, riots on the edge of the Niger Delta and sectarian violence in the north and centre of the country roughly split between a Muslim north and Christian south.
But observers had generally noted less thuggery and intimidation than in the run-up to 2007 polls.
The parliamentary elections are not as significant as those later this month, but they are fiercely contested by candidates who stand to win a pay package whose allowances alone top $1 million a year. Many Nigerians subsist on less than $2 a day.
Jonathan's ruling People's Democratic Party (PDP) is expected to see its parliamentary majority reduced. The PDP holds more than three-quarters of the 360 seats in the House of Representatives and of the 109 in the Senate.
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