1999 Ogun State gubernatorial electionThe 1999 Ogun State gubernatorial election occurred in Nigeria on January 9, 1999. The AD nominee Olusegun Osoba won the election defeating the PDP candidate.Olusegun Osoba emerged AD candidate.Electoral systemThe Governor of Ogun State is elected using the plurality voting system.Primary electionAD primaryThe AD primary election was won by Olusegun Osoba.ResultsThe total number of registered voters in the state was 1,592,502. Total number of votes cast was 403,260 while number of valid votes was 391,395. Rejected votes were 11,865.