DAKAR (Reuters) - Ghana’s main opposition party has nominated former President John Mahama to challenge incumbent Nana Akufo-Addo in next year’s election, a party official said on Wednesday, the third consecutive poll in which the two will face off.

Akufo-Addo unseated Mahama in a 2016 election, capitalizing on an economy that was slowing due to falling prices for gold, oil and cocoa exports.

Mahama, who succeeded his deceased predecessor in 2012 and defeated Akufo-Addo in an election later that year, accepted defeat immediately in 2016, maintaining the West African country’s record of fiercely contested but peaceful elections.

The National Democratic Congress’s (NDC) ticket designated Mahama its candidate for the December 2020 vote at a party congress over the weekend, its director of elections, Elvis Ankrah, told Reuters.

Akufo-Addo, who is expected to stand for re-election as the candidate of the New Patriotic Party (NPP), campaigned in 2016 on promises to cut deficits following overspending by Mahama’s government that blew a $1.6 billion hole in the budget.

He has presided over an economic recovery, with growth of 6.7 percent in the first three quarters of last year.

Ghana is the world’s second-largest cocoa producer, Africa’s number two gold producer and it began pumping oil off its coast in 2010.