In Nigeria, five more candidates say they will challenge President Goodluck Jonathan for the ruling PDP?s nomination in next year's presidential elections. They include a powerful former spy chief and four serving PDP governors.

All are from the north and say they are running to preserve the party?s zoning formula. Under zoning, the candidacy rotates between the north and the south. President Jonathan, a southerner, is serving out the rest of the first term of the late President Umaru Yaradua.

Some of the candidates have no chance of winning the PDP nomination but are running as ?political spoilers,? says Dr. Abubakar Momoh, who teaches political science at the Lagos State University.

Momoh disagrees with assertions by the candidates that they are in the race purely on personal convictions that they can move the country forward.

?By reputation and by political charisma, sagacity and carriage, some are paperweights, some are middleweights and some are heavyweights. Normally in this kind of situation, people are there to do spoiler politics. Others are sponsored by the big-wigs in order that when the contest gets heated, they can either step down or claim they are stepping down for other candidates in the interest of party unity.?

The fact that the candidates who have declared for the job are from a particular part of the country is significant, according to Momoh.

?There is an ideological perspective that is shaping towards that direction, namely that there is zoning and there is assumption that if it is zoning ? it about the north and it should be zoned to the north.?

He says claims by some analyst that the number of PDP candidates indicates a loss of power and influences by President Jonathan are unfounded.

?Even when former President Olusegun Obasanjo ran his first term and was due for re-election in 2003, quite a number of people stood against him.  So it is not true that it is because Jonathan is a weakling or people think he is not a formidable candidate.?