Iyiola Omisore, former deputy governor of Osun state, has defected to the All Progressives Congress (APC).
Omisore picked up the membership card of the ruling party at his polling unit in Ile-Ife on Monday.
He had contested the 2018 governorship poll on the platform of the Social Democratic Party (SDP) but came a distant third in the inconclusive election.
Initially, he had refused to throw his weight behind either the APC or the Peoples Democratic Party (PDP).
He later went into coalition with the APC before the September 28 rerun election.
The rerun held in seven polling units across four local government areas — Orolu, Ife north, Ife south and Osogbo.
Ile-Ife is the stronghold of Omisore, with the former senator enjoying enduringly loyal support in the ancient city.
Omisore served as deputy governor from 1999 to 2003 under Adebisi Akande and later as a member of the Nigerian senate for Osun-east from 2003 to 2009.