Nigeria's presidential election was shaping up to be a contest between two veteran male politicians, but the candidacy of Oby Ezekwesili could change that.Women have run for the presidency before but she is the most prominent Nigerian woman to challenge for the top job, the BBC's Nigeria reporter Chris Ewokor says.
Ms Ezekwesili is well known for leading the #BringBackOurGirls campaign to help free the 276 girls kidnapped from Chibok, northern Nigeria, in 2014. She has also served as the country's education minister and vice-president of the World Bank.
But come February's vote it will be a tough challenge to unseat incumbent President Muhammadu Buhari, 75, or beat the main opposition candidate, Atiku Abubakar, 72, who both have formidable party machines behind them.
The deadline to register for the election passed at midnight local time (23:00 GMT) on Sunday and at least nine candidates in all are thought to have submitted their papers.
At the weekend, President Buhari was nominated by his All Progressives Congress (APC) and Mr Abubakar beat a field of 11 others to become the flag bearer for the People's Democratic Party (PDP).
Read also:Nigeria Elections: Atiku Abubakar emerges PDP Presidential candidate
The two parties have supplied all of Nigeria's presidents since the end of military rule in 1999.