JOHANNESBURG – Former ANC president Thabo Mbeki is campaigning for the governing party ahead of the 29 May elections.Mbeki has urged South Africans to vote for the ANC.He says the party will attend to the problems facing the country.However, it must first attend to its internal problems.Mbeki was speaking on the campaign trail in Soweto.For the first time in 30 years, the ANC faces a real threat to its parliamentary majority, having steadily lost support in past elections.