Delays in issuing the results from Saturday's polls have led to further accusations by the opposition that Robert Mugabe, the country's president, has attempted to rig the vote.
The election commission is yet to announce any results in the race for the presidency.
However, the MDC announced its own tally and claimed on Monday that its results, based on counts posted at polling stations in 128 of the country's 210 parliamentary districts, showed it was leading presidential elections.
According to their results, Morgan Tsvangirai, the MDC leader, had 60 per cent of the votes compared to 30 per cent for Mugabe.
Tendai Biti, the MDC secretary-general, said that sources at the ZEC said rigging was under way, aimed at giving Mugabe a 52 per cent victory in the presidential race, and his party 111 of the 210 House of Assembly seats.
A presidential candidate needs at least 50 per cent plus one vote to avoid a runoff.
Biti said: "The people have spoken against the dictatorship. We are anxiously waiting for the final results.
"We pray that there will not be re-creation and re-engineering of the people's will."
The Zimbabwe Election Support Network (ZESN) said that according to data it collected from a representative random sample of 435 polling stations across 10 provinces, Tsvangirai was projected to get the highest number of votes followed by Mugabe - with Makoni coming a distant third.
Utoile Silaigwana, the deputy chief elections officer, declared partial results in a nationwide radio and television broadcasts on Monday.
The ZEC had said the delay was due to presidential and parliamentary elections being held at the same time, but the piecemeal announcement has left observers questioning the transparency of the process.
Kamahl Santamaria, reporting from Harare, the capital, said there was a lot of frustration considering that no word was heard from the ZEC for quite a while.
Al Jazeera's Haru Mutasa, reporting the town of Bulawayo, said that speculation was rife due to the delay in the announcment of results.
"This is an opposition stronghold, and they are hoping to win the presidential elections," she said.
|Some opposition supporters began celebrating |
after the MDC declared it was in the lead [AFP]
Ebrahim Fakir, a senior researcher at the Centre for Policy Studies in Johannesburg, told Al Jazeera that the delay in releasing results can be considered a win in the propaganda war for the opposition.
He also said that while it is against Zimbabwean law to declare an electoral victory before all results are released, the opposition are being "disingenuous", and the call of victory is a "rhetorical claim".
Fakir said: "We have also witnessed the lack of independent analysis and assessment of this election, and the lack of citizenry access to the political and democratic process in this country."
The US has "strongly encouraged" Zimbabwean authorities to properly count the election ballots cast.
Tom Casey, deputy spokesman for the State Department, said that Washington was concerned about "massive overprinting of ballots" and the deployment of police at polling stations in the lead-up to the elections.
Mutasa also said that if the MDC loses the elections, they will blame it on fraud.
"Many here believe the reason why results are taking so long is because government officials are trying to rig the elections."
Departure from past
Some election observers have said that initial results were known by 11pm (2100 GMT) on Saturday night, just four hours after polls closed.
In previous elections, partial results have been announced within hours of voting ending.
Notable early results included defeat for Patrick Chinamasa, Mugabe's outgoing justice minister, in the rural eastern constituency of Makoni central.
The MDC also won the first seat to be declared, the newly-formed constituency of Chegutu West, to the west of Harare.
Riot police patrolled Harare on Monday as the first results came in.
Before the polls, police said they would crush any premature celebrations but they were striking a softer line on Monday after a weekend of impromptu victory parties by MDC supporters.
"Police are very much still on high alert and appeal to those wanting to celebrate to do so with respect for other people," Wayne Bvudzijena, national police spokesman, said.
"It's human to celebrate but they should not provoke, intimidate or insult others."