Harare, Zimbabwe (CNN) -- Vote-counting in Zimbabwe's hotly contested election began late Wednesday with President Robert Mugabe and main challenger Morgan Tsvangirai confident of victory. Partial results were expected to come out early Thursday, said Rita Makarau, chairwoman of the Zimbabwe Election Commission, which has until Monday to release full results. Five presidential candidates are in the race including Mugabe and Tsvangirai, the current prime minister. Makarau dismissed allegations from Tsvangirai's party that the election commission rigged the polls for Mugabe. "I believe that the election is free and fair," she told journalists. "Maybe the reports that will come out will vindicate my view of the election as free and fair."
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NEW: Vote-counting begins late Wednesday
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NEW: Partial results are due early Thursday with full results due by Monday
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NEW: The head of the election commission says the vote was "free and fair"
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President Robert Mugabe's main challenger is PM Morgan Tsvangirai
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