What hope for democracy in Africa's most populous state?

NIGERIANS HAVE five days to decide who, as president, will lead them from military to civilian rule. The rest of the world - demob-happy at ending Nigeria's pariah status - is running out of time to decide what democratic guarantees to demand of the West African giant.

It matters. Nigeria is a world player. Ruled by the military for all but 10 of its 39 years of independence from Britain, Nigeria is the world's biggest black nation. It remains the fifth-biggest oil producer on the planet, with a population of more than 100 million. This population represents Africa's biggest market.

It gives us great footballers (Okocha, Babayaro), musicians (Fela, Seal) and writers (Soyinka, Achebe). But it could give much more. It could become a model for the kind of new, democratic Africa that we all want to see. Nigeria as an aspirational beacon for the values of the free world? Well, that is what we must hope for. It is why these elections are so crucial.

On Saturday, all around this vast and varied country, Nigerians will filter through green-and-white fabric booths and place their thumb-print beside the name of Olusegun Obasanjo's People's Democratic Party (PDP), or that of Olu Falae, now of the All People's Party.

In the local, gubernatorial and parliamentary elections so far, the PDP has been dominant. But now the race is between two men, and the voters' choices will be based largely on ethnicity or the allegiances of elders, not on issues.

Obasanjo is the 61-year-old retired general who in 1979 became the only military dictator to hand power to an elected government and was later imprisoned for an alleged coup plot against the late and tyrannical General Sani Abacha.

A Yoruba from the economically powerful south west, Obasanjo is viewed with suspicion in some parts of the country. Many Yorubas say he is a traitor who favours the northern ruling classes, dominant in the military top brass. In 1979, the man to whom he handed power was Shehu Shagari, a Hausa-Fulani from the north. In the east, he is viewed with caution. He headed a commando division in the Nigerian army which quashed Biafran independence there in the 1967-70 civil war.

But Obasanjo today brims with jocular charm, and has shrewdly endowed himself with a statesman's mantle. He has held prominent positions in various United Nations bodies and in the Commonwealth. He is on first- name terms with the former US president Jimmy Carter, who is an observer of these elections.

Obasanjo is allegedly funded by the military, especially the former dictator, General Ibrahim Babangida - cruel and corrupt in his day but now orchestrating the military's face-saving transition to civilian rule. Obasanjo's running- mate, Abubakar Atiku, may pacify some Yorubas. He was the northern kingmaker to their late hero, Moshood Abiola, winner of the presidential elections in 1993 which were promptly cancelled by the military.

Falae, aged 60, is in many ways dwarfed by his opponent. He is also hampered by the fact that pre-printed ballot papers give voters the confusing choice of three parties - the PDP, the APP and the Alliance for Democracy (AD), with which Falae started out.

Votes for AD will not be recognised on Saturday, the Independent Electoral Commission has ruled.

But Yoruba nationalism will hand him victory in Lagos and in Obasanjo's home town, Abeokuta. Thanks to his strait-laced running mate, Umari Ali Shinkafi, a Muslim conservative who was once the chief of the secret police, Falae will win the poor north east and north west.

Falae, a Yale-educated free-marketeer who believes that the best way to end corruption is to scrap official controls, served in the late Eighties as finance minister under General Babangida. Earnest, slightly humourless but intellectually razor-sharp, Falae is considered an economics wizard but is also blamed for having implemented a disastrous structural adjustment programme. He has strong Yoruba credentials for having backed Abiola in 1993 and having been imprisoned for "bomb-throwing" under General Abacha.

Even though both candidates have promised that there will be no witch hunts against embezzlers within the military, Obasanjo is their favourite. But a victory for Obasanjo could be too much to bear for the highly politicised and economically powerful south west.

If the Yorubas broke away so, probably, would the Igbos of the east, leading to chaos and maybe even civil war. Youths in the southern states who are currently kicking up rough against exploitation of their land by oil companies and the regime could easily channel their anger into rebel movements along Sierra Leonean lines.

On the other hand, a victory for Falae could be intolerable for the military, leading either to a puppet government or to a rerun of 1994 when General Abacha cancelled the poll which, the previous year, had elected President Abiola.

Even as the European Union and the United States give this Saturday's elections a clean bill of health - as they almost certainly will, despite documented discrepancies - the world must consider the many potential dangers that lie ahead.

Ever since General Abacha, in 1995, executed nine environmental campaigners, including Ken Saro-Wiwa, Nigeria has been the pariah state of choice for the Commonwealth and the United Nations. This Saturday's elections - likely to lead to a formal handover to civilian rule on 29 May - are supposed to mean an end to all that, and great opportunities for business. Royal Dutch/ Shell has already signalled its approval with a pledge to spend $8.5bn in Nigeria - sub-Saharan Africa's biggest-ever industrial investment.

But Nigeria, the world's fifth-greatest oil producer, will enter its new era on its knees, economically. The price of oil - the resource which accounts for 95 per cent of the country's exports - is now languishing at rock bottom. There is no infrastructure, while leprosy, Aids and illiteracy - all the worst ills of Africa - are widespread.

Political prisoners from Abacha's era still languish in jail and Human Rights Watch, in a report published today, will document continuing abuses. The country does not even have a constitution.

The success of Nigeria's transition to civilian rule will not be determined so much by who wins this Saturday's elections, as by how responsibly an eager outside world tailors its relationship with the demob-suited generals. It will be a vital task, and a novel situation for all concerned.