Nigerians are voting to elect a successor to President Muhammadu Buhari, with expectations that the next leader will steer Africa's most populous country and largest economy in a new direction.

Voting was supposed to begin on Saturday at 8:30 a.m. (0730 GMT), but there were accounts of delays of several hours in some locations, while voting proceeded more quickly in others.

Former army general Buhari is stepping down after spending the maximum eight years permitted by the constitution, but allegedly failing to fulfill his campaign promise to restore order and security throughout Nigeria, the continent's top oil-producing country.

The new president is anticipated to be chosen from among four of the eighteen applicants who have so far emerged as the leading contenders.

The three leading candidates in the race are former Vice President Atiku Abubakar, 76, of the major opposition Peoples Democratic Party, former governor of Anambra State Peter Obi, 61, of the smaller Labour Party, and former Lagos governor Bola Tinubu, 70, of the governing All Progressives Congress.

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As the country's voting age is 18 and older, Nigeria was anticipating that more than a third of all qualified voters, including the youth, would swarm the polling places, given that the country's voting turnout rate has consistently been low. Around 176,600 voting places in the National Assembly had more than 93 million voter registrations.

Amidst worries about intimidation, people are asking for an orderly and transparent electoral process as well as a peaceful transition of power.

Vote buying plagues elections

A Nigerian lawmaker was recently apprehended by the police in a key state along with almost $500,000 in cash and a roster of recipients. “Vote buying remains a major threat to our democracy,” Mahmood Yakubu, the head of Nigeria’s election commission, told reporters on Thursday.

Along with dealing with issues like high inflation, extreme poverty, and energy shortages, the incoming president will also have to deal with issues like large-scale oil theft in the south and widespread criminal activity everywhere.

As numerous armed groups continue their terror campaigns in at least four of Nigeria's six geographic zones, insecurity continues to be a major problem. In an attempt to increase security for the election, land borders were closed, troops were patrolling the streets in several states, and movements were limited.

The nation's economy, which has gone through two recessions in the last four years, is another key issue at stake.

Nigerians are coping with a cash shortage brought on by a botched plan to exchange old banknotes for new ones, which has disrupted people's everyday lives and resulted in violent scenes at banks and ATMs.