Cult of personality not limited to ruling parties
Kenya, over at Ambiguous Adventure, wonders 'Why Can't Opposition Parties in Africa Win?' She cites a BBC article which suggests two main categories: uneven playing fields and poor campaigning among opposition parties.
I think a lot depends on the country. In some cases, like Zimbabwe, the opposition is fairly unified and the greatest barriers come from government repression.
In other cases, the biggest challenge is a divided opposition. Guinea is the country I know best. There, each opposition party wants to protect its own turf and doesn't really work together. Sure, they issue joint communiques to denounce governmental repression, but they're united only in criticizing a common enemy not in trying to develop a common program or strategy for unseating that enemy.
Plus there's the fact that the main opposition leaders (except one) are the same as they were when multipartyism was introduced in the early 90s. The parties are little more than organs to promote particular individuals. After more than a decade, no major opposition party has had a change in leadership so routine in democracies. If you were to ask the ordinary Guinean about the ideology or principles of the UPR or the RPG, the two most prominent opposition parties, few would know. All most know is that the UPR is the Peul party and the RPG is the Malinke party and that they are strongest in Central and Upper Guinea respectively and that their leaders are Ba Mamadou and Alpha Condé.
The cult of personality isn't limited to ruling parties.