The vehicles were presented to Olajengbesi in Osogbo, the Osun State capital, on Thursday.
Olajengbesi disclosed the donation in an Instagram post on Friday, describing the gesture as unexpected.
He said D’Banj had contacted him about two weeks earlier to request the details of the person responsible for his campaign branding.
Olajengbesi said he assumed the request was connected to D’Banj’s CREAM initiative, which supports young creatives, and provided the contact details.
He said he was subsequently surprised when he received three fully branded Sienna buses from the singer.
According to Olajengbesi, he later contacted D’Banj to express his appreciation, with the entertainer describing the donation as “my token of support”.
The lawyer thanked the singer for the gesture, saying the vehicles would provide a significant boost to his campaign.
The donation comes as Olajengbesi prepares for a second attempt to secure election to the House of Representatives.
He previously served as spokesperson for Governor Ademola Adeleke’s re-election campaign during the 15 August 2026 governorship election in Osun State.
Olajengbesi is also the convener of the Imole Grassroots Mobilisation Network, a political mobilisation group in the state.
