By MacDonald Dzirutwe
HARARE (Reuters) - Zimbabwe President Robert Mugabe launched a "fight of our life" campaign on Friday to extend his three-decade grip on power in a July 31 election already being criticized as poorly planned, underfunded and plagued with irregularities.
Speaking to tens of thousands of supporters in a sports ground in Harare's Highfield township, the 89-year-old said his ZANU-PF party wanted to stay in office to push through its plans to increase black ownership of the economy.
Critics accuse Mugabe, who led the former Rhodesia to independence from Britain in 1980, of ruining one of Africa's most promising economies by seizing white-owned farms and giving them to landless blacks with no farming experience.
"This is the fight of our lives. This is a battle for survival," Mugabe told the crowd, adding that ZANU-PF had reorganized and strengthened itself for a "devastating victory" after nearly losing power five years ago.
"Those who work with our enemies, our former colonizers the British, never again shall we allow them to taste leadership of the state," he said.
Although there have been no formal opinion polls, surveys in the past year by Freedom House, a U.S. political think tank, and African research group Afro-Barometer have given Mugabe a narrow lead over his main rival, Prime Minister Morgan Tsvangirai.
The campaign launch comes a day after the Constitutional Court rejected appeals, including from Tsvangirai, to delay the vote in order to allow more time for reform of the security forces and state media.
The legal argument over the election date has raised fears of another disputed poll, although with just three weeks to go, there are few expectations of the kind of violence and bloodshed that marred the 2008 elections, after which Mugabe and Tsvangirai were forced into a power-sharing government.
Instead, Tsvangirai's Movement for Democratic Change (MDC) says the biggest threat is ZANU-PF "software rigging" - essentially tampering with the voters roll, or making it hard for MDC supporters to register to vote.
ZANU-PF have denied the allegations.
The MDC also alleges that some members of the army have been deployed in the countryside to intimidate potential opponents - a charge the security forces also deny.
In a 90-minute address on Friday, Mugabe urged ZANU-PF to avoid any violence, saying it was set to win cleanly.
He also mocked Tsvangirai with references to recent sex scandals and attacked the 15-nation Southern African Community (SADC) for trying to get Harare to delay the poll, saying it amounted to interfering with Zimbabwe's top court.
"Let it be known that we are in SADC voluntarily. If SADC chooses to do stupid and idiotic things we can pull out," he said.
Mugabe singled out South African President Jacob Zuma's top Zimbabwe adviser, Lindiwe Zulu, for particular criticism, saying she was behaving as if she were his country's prefect by saying Harare should postpone the vote by at least a month.
(Writing By Cris Chinaka; Editing by Ed Cropley and Gareth Jones)