AFRICA’S BIGGEST PRESIDENTIAL vote has got underway in Nigeria today with current leader Goodluck Jonathan seen as the frontrunner.

The continent’s largest oil producer will hope to have a free and fair election having long been plagued by corruption, vote fraud and violence during elections, BBC reports.

Jonathan’s main challenger is Muhammadu Buhari, who has strong support in the mainly Muslim north of the country.

Other challengers include former anti-corruption chief Nuhu Ribadu and Kano state governor Ibrahim Shekarau, though both are seen as outsiders to win the poll.

The winning candidate in the election must get a minimum level of support from across the enormous country of 150 million people which includes 73 million registered voters.

The electoral system is a complicated formula somewhat similar to the American electoral college system, AP reports.

The winning candidate cannot win the presidency outright unless he carries at least a quarter of the votes cast in at least two-thirds of states and the capital.

One of the main election issues is electricity with infrequent power supplies in part of the countries forcing some to use generators.

Last weekend the country held legislative elections in which violence erupted in the northeast where a radical Islamic sect operates, leaving a hotel ablaze, a politician dead and a polling station and a vote-counting center bombed.

- with additional reporting from AP