Jacob Zuma, Once Leader of the A.N.C., Becomes Its Political Rival

Jobless graduates, struggling business owners and army veterans marched through the eastern South African city of Pietermaritzburg this week, chanting the name “Jacob Zuma.”

The 500 or so demonstrators brought to a standstill parts of the city, in KwaZulu-Natal Province — the traditional stronghold of Mr. Zuma, a past president of both South Africa and the African National Congress, the party that governed the country for three decades.

Demanding water and electricity, the protest over commonplace local concerns was also a show of power for the new political party that Mr. Zuma now leads — uMkhonto weSizwe, or M.K. — with the hope of eroding the dominant position of his former allies.

“We are going to have to fight for things to change,” said Khumbuzile Phungula, 49, who joined the march after her neighborhood went weeks without water. “M.K. is all about change.”

As vendors sold Jacob Zuma T-shirts and an M.K.-branded energy drink, and men in the military fatigues of long disbanded anti-apartheid movements marshaled the crowd, the marchers embodied Mr. Zuma’s new party: a group of aggrieved voters who, like him, have fallen out with a governing party they view as ineffectual and corrupt. Mr. Zuma’s supporters now form a bloc large enough to turn him into a potential kingmaker in South Africa’s general election on May 29.

Not present at the Pietermaritzburg march was Mr. Zuma himself. Instead, he was preparing for a hearing at South Africa’s Constitutional Court on Friday about whether Mr. Zuma, 82, is eligible to stand at all. He resigned from the top office in 2018 amid widespread protests, and three years later was convicted and sentenced for failing to appear at a corruption inquiry, though in the end he served only two months of a 15-month sentence.