Ghana’s ruling National Democratic Congress (NDC) party nominated interim president John Dramani Mahama on Thursday as its candidate for a December presidential race, hoping a near-unanimous vote will restore unity after months of infighting.Mahama, who replaced the late president John Atta Mills as head of the cocoa, gold and oil-producing nation when he died last month, was the party’s intended candidate but had to be confirmed by a vote of the party congress in the town of Kumasi.He won 99.5 percent of 2,792 ballots cast in a vote that the party hopes will mend rifts that have centred mainly on a leadership challenge from the former first lady and wife of Ghana’s longtime ruler Jerry Rawlings.Mahama is expected to face a tough challenge from the main opposition New Patriotic Party candidate Nana Akufo-Addo."It is a massive endorsement and an overwhelming confidence-building in the candidate - a strong signal that the rank and file of our party are in a hurry to hit the campaign grounds,” deputy NDC general secretary George Lawson told Reuters.Akufo-Addo lost narrowly to Mills in 2008. Mills oversaw the start of oil production and Ghana’s economy is booming but he will be challenged on how much of the newfound wealth has trickled to ordinary Ghanaians.The congress, held in the second largest city of Kumasi, a stronghold of the opposition NPP, was attended by top officials of the party, clad in mourning clothes in memory of Mills.The Rawlingses have openly criticised Mills’s government for failing to tackle corruption and mismanagement. Nana Konadu Agyemang-Rawlings tried to win the NDC ticket in a December vote but Mills easily defeated her.