Abake Assongba, who has contributed more than $50,000 to Obama's re-election campaign this year, has been accused of defrauding a businessman and impersonating a bank official, federal records show.

She has been accused of thieving more than $650,000 to help build a multimillion-dollar home in Florida.

Mrs Assongba and her husband, Anthony J.W. DeRosa, run a charity called Abake's Foundation that distributes school supplies and food in Benin, Africa.

This is not the first scandal in Obama's campaign, his campaign help returned in March $200,000 last month to Carlos and Alberto Cardona, the brothers of a Mexican fugitive wanted on federal drug charges.