Atiku Abubakar's emergence as Presidential candidate for the biggest party challenging President Muhammadu Buhari in Nigeria's elections in February guarantees a lively contest for voters but little else. For Atiku, 71, and Buhari, 75, it is a final roll of the dice; for their followers it will be a demanding test of campaigning skills and political organisation. A better-run electoral commission and voter registration process with biometric technology have made elections more competitive over the past five years.

Those who insist Nigeria's presidential battle is more about personalities than policies are only half-right. There is a distorting mirror between Buhari's All Progressives Congress – seen as tough on corruption but anti-business – and Atiku's People's Democratic Party – seen as weak on corruption but pro-business. As the owner of a major logistics and IT company, Atiku has strong business support. Buhari's tough line on international companies and big banks plays well with poorer voters.

If Buhari's APC benefits from a consensus behind his candidacy, there are glaring divisions further down the hierarchy which could hit its campaigning strength. Nine of the party's state governors called for a meeting with Buhari to complain about the management of primary elections in the states; that is, their candidates lost. The PDP is a much more unified party at state level but Atiku's biggest task is to persuade all the party's rival presidential contenders to close ranks behind him.