Mr Ubah, a former governorship candidate in the state, defeated his closest rival, Chris Uba of the Peoples Democratic Party (PDP) who got 62,462 votes.
Nicholas Ukachukwu, the All Progressives Grand Alliance (APGA) candidate, polled 51,269 votes while the All Progressives Congress (APC) candidate, Andy Uba, got 13,245 votes.
Announcing the result at the collation centre in Nnewi North local government area, M.N Umenweke, the returning officer, said Mr Ubah emerged the winner among the 26 candidates who contested for the ticket.
“Mr Patrick Ifeanyi Ubah of the YPP having satisfied the requirements of the law and scored the highest number of votes is hereby declared the winner and returned elected as the senator representing Anambra South,” Mr Umenweke, a professor at the Faculty of Law, Nnamdi Azikiwe University.
Andy Ubah is currently representing the zone in upper chamber of the National Assembly.