DA leader John Steenhuisen over the weekend announced Zille as Joburg mayoral candidate. ALSO READ: Helen Zille to run for Joburg mayor as DA vows to ‘wrestle city back’Who will partner with the DA? The halo effect is a psychological bias where the positive image of one person spills over onto others associated with them. There is no clarity yet on who will be the DA’s candidate in Ekurhuleni, or whether Cilliers Brink will be confirmed for Tshwane. READ NEXT: ‘Let’s fix the basics of Jozi’ – Helen Zille eyes Joburg mayoral race