Sahara Reporters describes the PDP primary and convention as essentially an auction for the presidential nomination.
Based on the 2006 convention, this description rings true. However, I suspect that the size of the individual bribes is understated, and that there is plenty of intimidation as outlined in a plan that includes as many sticks as carrots. The Jonathan and Abubakar camps each accused the other of being its author. But nobody denied its likely veracity.