By Joe Brock and Camillus Eboh
ABUJA (Reuters) - Nigerian President Goodluck Jonathan took an early lead on Friday as votes were counted from the ruling party primaries, although his main rival's camp raised questions about the conduct of the poll.
The vote pits Jonathan, the first head of state from the southern oil-producing Niger Delta, against ex-Vice President Atiku Abubakar, a businessman from the mostly Muslim north, in a race that has split the People's Democratic Party (PDP).
Jonathan had a commanding lead with votes counted from 11 of the country's 36 states, although most of them were in the south and centre. Atiku won two of the 11 states, Sokoto and Zamfara in the north, but lost his home state of Adamawa.
A simple majority of the delegates' votes -- expected to total as many as 4,000 -- wins. Jonathan had 715 votes against 276 for Abubakar with the 11 states in.
Abubakar's supporters said the counting process -- reading out results state by state -- favoured the incumbent because it put pressure on state governors, who depend on federal resources to fund their own budgets, to back the president.
"It is a grand design to rig. We only found out about it when we arrived here. We asked for a full delegates' list, which we never got," said Umar Kareto Lawan, an Abubakar supporter from the northeastern state of Borno.
Jonathan's supporters dismissed the complaints.
"There will always be complaints ... Complaints should be made before, not after," Foreign Minister Odein Ajumogobia said.
The PDP candidate has won every presidential election in Africa's most populous nation since the end of military rule in 1999, meaning victory in the primaries has in the past been a virtual guaranteed ticket to the presidency.
But Jonathan's accidental ascent 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.
POLARISED DEBATE
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 campaign manager, Ben Obi, complained of irregularities before voting began, saying the delegates' lists had been doctored, and Abubakar himself made a fiery speech at the convention condemning Jonathan for breaching the zoning pact.
"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," he said, raising doubts about whether he would quietly accept defeat and back Jonathan.
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.
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.
Analysts fear the election debate could become polarised around north-south rivalries if parts of the PDP turn their back on Jonathan should he win the primaries.
(Writing by Nick Tattersall; Editing by Jon Hemming)
