Although there are many presidential candidates, analysts say Mr Buhari's main contender is former Vice-President Atiku Abubakar.
Inkastoo ay jiraan murashixiin badan, haddana dadka wax falanqeeya waxa ay sheegayaan in ninka loollanka ugu adag kula jira Mr Buhari uu yahay madaxweyne ku xigeenkiisa Atiku Abubakar.