Nigerian President Muhammadu Buhari arrives for an anti-corruption summit in London in May 2016.
Dan Kitwood/Getty Images

In photos: Nigerian President Muhammadu Buhari

Updated 11:29 AM ET, Mon February 18, 2019

Nigerian President Muhammadu Buhari arrives for an anti-corruption summit in London in May 2016.
Dan Kitwood/Getty Images

After a one-week delay, Africa's most populous nation goes to the polls this weekend to vote in a presidential election.

Seeking re-election is Nigerian President Muhammadu Buhari, a 76-year-old former army general who defeated Goodluck Jonathan in 2015.

Buhari is running against 71 other candidates, but his main challenger is Atiku Abubakar, a business tycoon and former vice president. Both men are Muslims who hail from the same ethnic group, but they are opposed ideologically.

Nigeria returned to democracy in 1999 after decades of military rule. When Buhari defeated Jonathan in 2015, it was the first time an incumbent had ever lost an election and there was a peaceful transition of power to the opposition leader.

Now it's Buhari who is the incumbent.