South Africans were on edge Thursday as votes trickled in from a tight national election, with early returns showing poor results for the African National Congress, the party that has governed the country for three decades.
While official results are not expected before the weekend, projections show that the party, known as the A.N.C., is likely to draw under 50 percent of the vote, down from 57.5 percent in the last election five years ago.
That would mean the A.N.C. — for the first time — would need to form a coalition with one or more rival parties in order to stay in power. In South Africa’s parliamentary system, President Cyril Ramaphosa, the leader of the African National Congress, would need the support of members of the opposition in order to serve a second term.
A weakened A.N.C. would significantly change South African politics, and also its policies, shifting the country away from a government dominated by a single party to one held together by fragile coalitions. This strategy has worked for the A.N.C. in small municipalities, but has been fraught in large cities like Johannesburg, where it has led to political infighting.
With about half of all voter districts counted, the early results showed the A.N.C. with 43 percent, and trailing in critical provinces that it won handily in the last election.
These early results for the A.N.C. stem largely from rural regions that have remained loyal to the party. In South Africa’s most populous province, Gauteng, only 12 percent of voting districts had confirmed their results by Thursday.
There are 51 opposition parties vying for voters. The largest, the Democratic Alliance, is led by John Steenhuisen, a white politician in a majority-Black country. Before the election, the Democratic Alliance formed an alliance with smaller opposition parties.
Without support from the Democratic Alliance, the A.N.C. may have to form a coalition with the next-largest opposition party, the Economic Freedom Fighters, a leftist party that has strong support among young voters. Its leader, Julius Malema, formed the Economic Freedom Fighters in 2013 after he was expelled from the A.N.C.’s youth league.
A new party, uMkhonto weSizwe, or M.K., led by former President Jacob Zuma, who also broke away from the African National Congress, showed early strength in Mr. Zuma’s home province of KwaZulu Natal. Mr. Zuma’s daughter, Duduzile Zuma-Sambudla, recently said that the M.K. party would not work with Mr. Ramaphosa.
Some analysts have not ruled out that the A.N.C. may yet win over 50 percent of the vote. The party could also claw back support in provinces like the Eastern Cape and Limpopo, giving it more negotiating power with opposition parties.
The election comes 30 years after the end of apartheid, at a time when South Africa’s economy is sluggish, youth unemployment is high and the national mood is low.
On Election Day on Wednesday, lines snaked around polling stations. New voting regulations and an additional ballot to fill out caused delays, the election commission acknowledged. Yet by 9 p.m., thousands of South Africans remained in line as polls were closing, braving the chilly autumn air as they waited for their chance to vote. The electoral commission said early figures showed voter turnout to be higher than in the last national election, held in 2019.
“We’re fed up,” said Isabel Olatunji, pushing her infant son in a stroller as she waited at a polling station in a suburb of northern Johannesburg. Ms. Olatunji, 32, said she was “60 percent optimistic” that the election would bring change, or at the very least, she said, “get the ball rolling.”