The disillusionment with the African National Congress has been gradually building over the years and has intensified during labor unrest in recent weeks, The Washington Post reported Saturday.
"Now, the honeymoon is pretty much over," said Robert Schire, a political analyst at the University of Cape Town. "What we are seeing is that the average black South African is no longer blindly loyal to the ANC. That person feels angry and betrayed."
The ANC promised sweeping social change to correct the inequalities created under apartheid, but many black South Africans still struggle without jobs, a lack of housing and education, clean water and other services, analysts say.
ANC officials say their policies have significantly decreased poverty throughout the country, but they are still facing obstacles.
"In terms of giving access to basic services, we have done well," said Keith Khoza, a senior party spokesman. "At the [same time], we acknowledge the task of reversing an apartheid and colonialist legacy that spanned over 300 years is not going to happen overnight."
There is also a mistrust of the party's leadership over corruption allegations, said Jay Naidoo, a former general secretary of the Congress of South African Trade Unions and senior ANC leader.
"The fact is that there is a deep and growing mistrust of leaders in our country, and the expanding underclass feels it has no voice through legitimate formal structures," he wrote on his blog. "Violence becomes the only viable language."
Many black South Africans say they are so frustrated that they will vote against the ANC.
Mbongiseni Dlamini, a 29-year-old miner who has participated in recent strikes, said he voted for the ANC in the last elections, but he now plans to vote for the Democratic Alliance.
"The DA is not just for white people," he said. "We want a party that will bring change, and the ANC has failed us."