Nigeria’s main opposition party has won the governorship election in southwest Osun state, the electoral commission said on Sunday, in a major upset to President Muhammadu Buhari’s ruling All Progressives Congress. Osun is one of eight of Nigeria’s 36 states where governorship elections are not being held at the same time as the rest of the country because of legal challenges to previous results. The Independent National Electoral Commission (INEC) said Senator Ademola Adeleke of the Peoples Democratic Party (PDP) polled 403,371 votes to unseat incumbent APC governor Gboyega Oyetola, who scored 375,027 in Saturday’s ballot. “I declare … that Ademola Jackson Nurudeen Adeleke of the PDP, having satisfied the requirements of the law, is hereby returned elected,” INEC returning officer Oluwatoyin Temitayo Ogundipe said. Adeleke, 62, won 17 of the state’s 30 local government areas while Oyetola won in 13. The announcement sparked spontaneous celebrations on the streets of Osogbo, the state capital. PDP supporters sang and danced and motorists blared their horns. Buhari on Sunday congratulated Adeleke, who became the 10th governor since the creation of the state in 1991. “With the election over, the president expresses conviction that the people of Osun have expressed their will through the ballot, and the will of the people must always matter and be respected in a democracy,” Buhari’s office said in a statement.