South Africa's ruling African National Congress (ANC) has sealed its fifth successive victory in the national election securing 62% of the votes despite opposition gains.

Jacob Zuma is set to start his second five-year term as South African president.

The provisional results announced by the electoral commission showed the main opposition Democratic Alliance (DA) garnering 22.22% of the votes with the leftist Economic Freedom Fighters (EFE) managing to secure 6.35%.

Although the ruling ANC has won this election with a thumping majority, the opposition parties have made major gains from previous occasions.

"We are on track to achieve our historic mission of realigning politics and unseating the ANC from national government in the next decade," said Helen Zille, leader of DA, which won 16.7% of the votes in the last election.

South Africa has 25 million registered voters and 73% turned out to vote on polling Wednesday (7 May). An independent observer mission from the African Union had earlier declared the polling "free, fair, transparent and credible".

The results are on widely predicted lines. This is the first election since the death of anti-apartheid leader Nelson Mandela who belonged to the ANC.

"We are still the party that restored the dignity of our people in this country. People will never forget that. We are very humbled by the confidence the people have shown to the African National Congress," ANC spokesperson Jackson Mthembu told Al Jazeera.

Although the ANC enjoys widespread popularity, the Zuma-led administration has been hit by serious controversies recently.