Tensions are high in the southern African state that has never seen a transition of power since Mugabe led the country to independence in 1980.

The Zimbabwe Electoral Commission's delay in releasing the presidential count raised suspicions that Mugabe's government was buying time to rig the results, something many believe was done in 2002, when Mugabe last faced Tsvangirai.

"The people of Zimbabwe will not allow such a thing to happen," said Thoko Khupe, vice president of Tsvangirai's Movement for Democratic Change (MDC) Party. "They are not going to accept that. They now know that they won this election."

According to an independent African monitor, senior members of Mugabe's party are worried the government may have lost the elections, The Associated Press reported.

Marwick Khumalo, head of the Pan-African Parliament observer mission, indicated the ruling ZANU-PF party was considering the possibility of defeat, the agency said.

"I was talking to some of the big wigs in the ruling party and they also are concerned about the possibility of a change of guard," he told the South African Broadcasting Corporation's SAfm radio, the agency reported.

MDC sources denied to CNN that it was in talks with the Zimbabwean leader over a possible transfer of power, in spite of a report Tuesday on the New York Times' Web site that Mugabe was preparing to cede power to Tsvangirai.

The long delay in results has left Zimbabweans desperate for information.

Cashing in on the public demand for news of the vote, vendors sold the state-run newspaper The Herald for three times the official cover price.

In spite of the information blackout for the presidential vote, the commission released updated results for the parliamentary election Monday.

With 109 seats out of a total of 210 declared, Mugabe's Zimbabwe African National Union-Patriotic Front (ZANU-PF) had won 53; the MDC 51; and a party that split from the MDC had five seats.
Watch Zimbabwe's opposition vows that election won't be stolen

British Prime Minister Gordon Brown urged a quick report on results, saying "all eyes will be on Zimbabwe."

"I think there are two things that are important: The results come forward soon and they are not delayed. Secondly, that the election seems to be fair and representative."

In the absence of official presidential results, a group of non-governmental organizations monitoring the election released exit polling data that showed Tsvangirai leading.

Noel Kututwa, chairman of the Zimbabwe Election Support Network, said that his group's polling data gave Tsvangirai 49.4 percent of the vote -- short of the 50 percent plus one vote needed to avoid a runoff election.

Mugabe was second with 41.8 percent. Independent candidate Simba Makoni had 8.2 percent.

The MDC declared victory Sunday, saying results posted at precincts around the country gave Tsvangirai 67 percent of the vote.

"Results are posted at each and every polling station. It is now public knowledge that the MDC has already won this election. It is not something that is private. Everybody knows that, so how can you steal something which is already in the public's eye," MDC Vice President Khupe said.

One major concern is how Mugabe, 84, or the military would react to electoral defeat.

"The key thing now is whether behind the scenes how the army is reacting, whether they're going to back up ZANU-PF and say 'We're going to keep Mugabe at whatever cost' or whether really now they know the game is up," said British Parliament member Kate Hoey, a frequent visitor to Zimbabwe.

A year after the last presidential election -- which the MDC said was stolen -- the government of Zimbabwe charged Tsvangirai for treason. He was acquitted. The MDC accused Mugabe of trying to eliminate him as a challenger.

Zimbabwe faced international sanctions after the 2002 election, including travel restrictions imposed by the United States on Zimbabwean officials.

The Commonwealth - made up of Britain and its 53 former colonies - suspended Zimbabwe, prompting Mugabe to withdraw from the group.

"The world can't sit by this time and allow Mugabe to steal another election," Hoey said. "It just isn't going to happen. I really can't see this time, because the majority is going to be so much bigger and the people of Zimbabwe are peaceful people and really want to see this change happen. We must support them."

Hoey said the United Nations needs to get involved, as well as South Africa and other neighboring nations.

The United States, which has raised concerns about election fraud, called on Zimbabwe's government to make sure "the counting of the votes ... ensures the will of the people is heard," State Department spokesman Tom Casey said Monday.

While election observers have urged prompt reporting of the results to avoid political unrest, government officials said it takes time to verify and "harmonize" the counts.

It is unlikely that if Mugabe emerges as the victor, he will receive any congratulations from the United States.

Speaking to reporters during her trip to the Middle East, U.S. Secretary of State Condoleezza Rice called the longtime president and his government "a disgrace to the people of Zimbabwe and a disgrace to southern Africa and to the continent of Africa as a whole."

The Zimbabwean government has denied CNN and other international news organizations permission to enter the country to report on the elections.

A hero of the country's civil war against the white Rhodesian government, Mugabe became the country's first black leader in 1980. Nearly three decades later, he has consolidated his rule over all aspects of Zimbabwean life.

His country was once revered for offering its citizens some of the best education and health care in Africa, but now schooling is a luxury and Zimbabwe has one of the lowest life expectancies in the world.

Zimbabwe was once known as the breadbasket of southern Africa, but now it is difficult to get even basic food supplies. Inflation has skyrocketed to more than 100,000 percent, while food production and agricultural exports have dropped drastically.

Mugabe denies mismanagement and blames his country's woes on the West, saying sanctions have harmed the economy.