Jacob Zuma on Sunday used a final rally before his near-certain victory in Wednesday’s elections to pledge to uphold the independence of South Africa’s judiciary, as he whipped up huge crowds of supporters electrified by the surprise appearance of Nelson Mandela.

The atmosphere at a packed Ellis Park, Johannesburg’s 60,000-seat rugby stadium, reflected the scale of victory the African National Congress expects to secure. Leaders of the party that has ruled since the end of apartheid in 1994 say they are confident of repeating the two-thirds majority they won in the last polls five years ago.