March 28 (Bloomberg) -- Simba Makoni's decision to run for president of Zimbabwe in tomorrow's election represents the biggest split in Robert Mugabe's party since it took power 28 years ago. And the beneficiary may be Robert Mugabe.

Even as Makoni's candidacy demonstrates the 84-year-old incumbent's tenuous hold on the ruling Zimbabwe African National Union-Patriotic Front, it is sapping support from former labor leader Morgan Tsvangirai's opposition Movement for Democratic Change.

``They should have formed a united front,'' said Chris Maroleng, an analyst at the Pretoria, South Africa-based Institute for Security Studies, a donor-funded research institute. Makoni is ``not good news for Tsvangirai, and Tsvangirai is not good news for him.''

Mugabe, who defeated Tsvangirai by 56 percent to 42 percent six years ago, is seeking to extend his 28-year rule, which has given Zimbabwe more than a decade of recession and an inflation rate of 100,580 percent.

Parliamentary and municipal balloting takes place on the same day. The leading presidential candidate must win more than 50 percent of the vote or face a runoff against the nearest challenger three weeks later.

The last three elections were marred by irregularities and violence, according to European Union observers at the time. Zimbabwe Human Rights NGO Forum and New York-based Human Rights Watch say this election will be no better.

`Relentless' Suppression

``Over the last 12 months there has been relentless violence and suppression,'' Harare-based Zimbabwe Human Rights said in a March 20 report.

Invitations sent to election observers excluded the U.S. and European countries except Russia. Most news media were refused visas to cover the balloting.

``Would Mugabe allow this election to happen if he wasn't certain of winning it?'' said Richard Dowden, director of the London-based Royal African Society. ``Too many people in positions to fix the election have too much to lose to allow anyone else to win.''

Mugabe's government dismisses the criticism. ``The country is so peaceful, there is so much tranquility,'' Simon Khaya Moyo, Zimbabwe's ambassador to South Africa, said in Johannesburg on March 20. ``This is to the chagrin of our detractors, led by London and Washington.''

Makoni, 58, was the youngest member of Mugabe's cabinet at independence in 1980, and later worked as a top executive for the Southern African Development Community and Zimbabwe Newspapers Ltd.

Ndebele Support

He has the backing of a dissident MDC faction supported by the minority Ndebele people in the south, including former Home Affairs Minister Dumiso Dabengwa. Makoni's origins in Zimbabwe's east may win votes in an area that favors opposition parties.

Tsvangirai, 56, has refused to join forces with Makoni, who is running as an independent, because of the latter's links to Mugabe's Zanu-PF. Under Mugabe's government, Tsvangirai was charged with treason in 2002 and 2004, and acquitted both times.

``I and Zanu-PF are like oil and water; we don't mix,'' Tsvangirai told reporters in Johannesburg on Feb. 13. ``Makoni is just as guilty as the rest of Zanu-PF's elite.''

Nkosana Moyo, Makoni's campaign manager, on March 26 said Makoni and Tsvangirai would combine forces if the contest comes to a runoff. Nelson Chamisa, a spokesman for Tsvangirai, declined to comment.

Urban Residents

Tsvangirai's main support comes from Zimbabwe's urban residents, who have been hard hit by rising food prices and fuel shortages. In the capital of Harare, Mugabe's government forcibly removed 700,000 slum dwellers in a 2005 campaign known as Operation Murambatsvina: ``no tolerance for dirt.''

Ndebele Zimbabweans oppose Mugabe because of a military campaign in the early 1980s that quelled Ndebele rebels and resulted in the deaths of as many as 20,000 civilians, according to the Catholic Commission for Justice and Peace.

Makoni says he will draw from the ruling party and the MDC. ``I have the support of a large majority of Zimbabweans, including Zimbabweans in Zanu-PF and the MDC,'' he said in an interview this month.

``Clearly, he is going to split the anti-Mugabe votes,'' said Sebastian Spio-Garbrah, an analyst at Eurasia Group, a New York-based political-risk firm. Tsvangirai in a Feb. 13 interview said he expects Makoni to take votes only from Mugabe.

Redistributing Land

The president's support remains strong in the Shona- dominated north of the country. There, his policy of seizing white-owned commercial farms and redistributing them to black subsistence farmers has proved popular even as it pushed the country into recession. Zimbabwe, once the continent's second- biggest corn exporter after South Africa, has been turned into Africa's biggest corn importer.

Even if Mugabe holds onto power after the election, he still might leave his post under pressure from his party as the country's economic crisis deepens. In the past, he has sent mixed messages about stepping down: In April 2005 he said he would retire at his term's end this year, then in February 2007 he said ``there's no vacancy'' for the post of Zimbabwean leader.

To contact the reporters on this story: Antony Sguazzin in Johannesburg at asguazzin@bloomberg.net; Brian Latham via Johannesburg at asguazzin@bloomberg.net.

Last Updated: March 27, 2008 18:00 EDT