* No incumbent has lost an election bid
* Historically the primary is the key vote
* North-south rivalry divides the party
* Results expected in early hours of Friday
(Recasts with counting underway)
By Joe Brock and Camillus Eboh
ABUJA, Jan 13 (Reuters) - Nigeria’s ruling party began counting votes late on Thursday to decide whether President Goodluck Jonathan will be its candidate in April elections, in one of the most divisive races for more than a decade.
Delegations from each of Nigeria’s 36 states voted one by one at the People’s Democratic Party (PDP) convention in a floodlit parade ground in the capital Abuja. A simple majority wins and results are expected early on Friday.
Such is the political dominance of the PDP that whoever wins its primaries has always gone on to be the country’s next ruler.
Historical precedent is on Jonathan’s side. Should he be defeated in Thursday’s vote, he would be the first sitting president to lose an election bid in the nation since independence from Britain in 1960.
“He’s very confident. He was up all night visiting all the delegates ... He only finished about 9 a.m. this morning,” Jonathan’s campaign spokesman Sully Abu told Reuters.
But Jonathan’s accidental route to power — assuming the country’s highest office when his predecessor, Umaru Yar’Adua, died last year — means Nigeria is in uncharted waters.
His bid interrupts a PDP pact that power rotates between the mostly Muslim north and largely Christian south every two terms. As a southerner, he faces opposition running for what would have been the second term of Yar’Adua — a northerner.
His main rival, former Vice President Atiku Abubakar, a wealthy businessman from the northern Hausa ethnic group, tore into Jonathan, accusing him of ripping up the rule book.
“If rules can be thrown away by just anyone who feels he is powerful enough to do so, then it is an invitation to lawlessness and anarchy,” Abubakar told the convention.
Profile of President Goodluck Jonathan [ID:nLDE70B2GK]
Profile of candidate Atiku Abubakar [ID:nLDE70B2GQ]
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Twenty of the 27 PDP state governors have publicly said they will back Jonathan. Many of the delegates arriving for the convention said the same, but there is no way of telling whether they will ultimately do so at a secret ballot. [ID:nLDE70B1VP]
Should Abubakar lose, he could form an alliance with a rival party and take northern support with him, going on to challenge Jonathan at the general elections.
His camp complained of irregularities before voting began.
“The delegates’ list has been doctored. Delegates have been taken off the list,” his campaign director Ben Obi said, but declined to comment on whether he would challenge the outcome.
Africa’s most populous nation is a patchwork of more than 200 ethnic groups, roughly equally divided between Christians and Muslims, who generally live peacefully side by side.
But regional and ethnic rivalries bubble under the surface and can easily be exploited by power-hungry politicians.
“This election is one of the most important in Nigeria’s struggle to consolidate its fledgling democracy,” said Dapo Oyewole, of the Centre for African Policy and Peace Strategy.
“It sees a highly contentious shift of power from the north to the south, breaking the informal zoning rotational agreement between these two regions that have competed for power since independence,” he said.
As a band played, delegations from each of the 36 states lined up to choose between Jonathan, Abubakar, and Sarah Jibril, the only female candidate and seen as a rank outsider.
Helicopters buzzed overhead and the secret service, soldiers and riot police sealed off streets around the venue.
Nigeria has been rocked by violence as the election season gets underway, unrest which Jonathan’s supporters suspect has been orchestrated to undermine his credibility.
A New Year’s Eve bomb in Abuja killed four people. A series of blasts and subsequent clashes have killed more than 80 in the central city of Jos, the scene of frequent bursts of ethnic and religious unrest. [ID:nLDE701085]
The stakes in Thursday’s vote are high and the outcome far from certain. But few expect the country to tumble into chaos.
“Nigeria has this inexplicable capacity to totter on the tip of anarchy, but fall back into an unexpected order of sorts,” said Oyewole from CAPPS.
"It's a country where everything and anything can happen." (For more Reuters Africa coverage and to have your say on the top issues, visit: af.reuters.com/ ) (Writing and additional reporting by Nick Tattersall in Lagos; editing by Angus MacSwan)