​​South Africa’s ruling African National Congressis at risk of losing control of a second key city in local elections tomorrow, weakening its 17-year grip on power.

The southern coastal city of Port Elizabeth, the biggest in the home province of former ANC leaders Nelson Mandela and Thabo Mbeki, may fall to the main opposition Democratic Alliance, said analysts including the University of Johannesburg’s Adam Habib. The ANC’s share of the city’s vote slipped almost 30 percentage points to just over half in general elections in 2009 from 2004.

Losing Nelson Mandela Bay municipality, which contains Port Elizabeth, means “the stranglehold the ANC has on the electorate is broken,” said Habib in an interview in Johannesburg yesterday. “We know Nelson MandelaBay is up for grabs. It would be an amazing slap in the face.”

After securing an end to white minority rule in Africa’s largest economy in 1994, the ANC has won a clear majority in every election since then. Its support though is waning as unemployment climbs and inequality persists. Electoral losses may tempt the ANC to weaken its business-friendly policies, said Razia Khan, head of Africa research at Standard Chartered.

Labor unions have pushed the ANC to increase spending to help find work for the one in four without a job, while the ANC Youth League is lobbying for greater state control of the economy, such as nationalizing mines operated by companies such as Anglo American Plc (AGL), the world’s biggest platinum producer.

“At the back of a lot of people’s minds has always been the idea that if push comes to shove, when the ANC finally found itself more pressured in a political sense, then maybe that adherence to market-friendly policy will give a little,” Khan said in a May 6 interview in Cape Town.

After a stock market and currency rally last year, South Africa’s rand lost 5.9 percent against the dollar in the year through last week. The stock exchange in Johannesburg has fallen 0.5 percent in the same period.

Zwelinzima Vavi, general secretary of the Congress of South African Trade Unions, the country’s biggest labor federation, said there was a “real danger” the ANC may lose control in Port Elizabeth, the Sowetan newspaperreported on April 6.

The ANC’s share of the national vote may drop to 59 percent from 66 percent in 2006, according to a survey from polling company Ipsos (IPSOF)released yesterday. Of the 2,050 likely voters surveyed from mid-April, 19.3 percent said they’d vote for the Democratic Alliance. The DA won 14.8 percent five years ago.

Party leader and Western Cape provincial head Helen Zille is betting the DA’s track record in Cape Town, which it has controlled since 2006, can win it more votes.

“I’m going to vote for the DA, 100 percent,” said Zoleka Ngetu, a 38-year-old maid in Port Elizabeth. “I voted for the ANC for a long time, but I’ve now lost trust. There is a lot of corruption; housing is very poor; they don’t fix anything; the roads are terrible. People are very, very tired.”

The ANC has been dogged by allegations of corruption. The Johannesburg-based Sunday Timesreported on April 10 that Sicelo Shiceka, the minister in charge of local government, spent hundreds of thousands of rand of taxpayers’ money on luxury hotels, flights for his family and visits to a girlfriend in a Swiss jail. He hasn’t commented on the allegations and ministry spokeswoman Vuyelwa Qinga didn’t respond to messages left on her mobile phone.

Meanwhile, many township dwellers feel their lives haven’t improved since the end of apartheid, with residents in Ermelo in the eastern Mpumalanga province, blocking roads with burning tires in demonstrations in February. South Africahad a record 111 such protests last year, according to Johannesburg-based Municipal IQ, an independent local government research group.

South Africa’s Gini coefficient, a measure of income inequality, is 0.68, according to the Treasury, one of the highest in the world and higher than at the end of apartheid. A reading of zero means income equality, while a reading of one means complete inequality.

A dip in ANC support won’t threaten the party’s national majority, which stood at almost two thirds in 2009, according to Habib.

President Jacob Zumaon May 9 said the DA are “daydreamers,” when asked if they had a chance of winning Port Elizabeth or any other city.

Many black South Africansremain loyal to the ANC because of its decades-long struggle against apartheid and the racial nature of politics in the country, according to Steven Friedman, director for the Johannesburg-based Centre for the Study of Democracy.

“Politics in this country is very much about identity; that you’re voting for someone who has a similar background to you,” Friedman said in an interview. Zuma on May 15 told tens of thousands of ANC supporters that every vote for his party says “we don’t want to go back to the era of racism.”

In a country where almost 80 percent of the population is black, only one member of the DA’s 10-person leadership is black, while 66 of its 77 lawmakers are white or mixed-race. The DA is trying to promote blacks within the party to woo more voters.

Regardless of the outcome in Port Elizabeth, “the ANC will have been served notice: in future, service delivery failure will be punished by the voters,” DA leader Zille said in a May 8 statement. “There will no longer be a free ride for any party in South Africa.”