Kenya's police commissioner has urged poll losers to respect the outcome as counting continues in elections seen as the country's closest ever.
Voter turnout is thought to have been more than 70%
Vice-President Moody Awori and other ministers have lost their parliamentary seats, preliminary results indicate.
The presidential race between Mwai Kibaki and his main challenger, Raila Odinga, is too close to call.
Mr Odinga's Orange Democratic Movement has accused the electoral commission of deliberately delaying the results.
ODM General Secretary Joseph Nyaga said the delay threatened to cause instability and unrest right across the country.
Despite a campaign marred by violence and vote-rigging allegations, observers say polling day itself was well organised and largely peaceful.
A spokesman for Electoral Commission of Kenya (ECK) told the BBC that turnout had perhaps been more than 70%, from an electorate of 14m.
Police Commissioner Hussein Ali said it was now time to start the healing process and said those who felt aggrieved should take their case to court, not the streets.
"For the winners, we trust that you will exercise magnanimity in your victory and for the losers, to understand and realise that the democratic process has winners and losers and they can always try some other time," he told a press conference shown on KTN television.
"It is after all an election. It is not permanent enmity," he said.
The BBC's Adam Mynott in the capital, Nairobi, says results have emerged very slowly.
Only a handful have been officially announced by the ECK, but results of polling are being reported steadily by radio and television stations.
Mr Nyaga says the ECK is deliberately withholding the results, which are not official until they are declared by the commission.
"We would like everything to be out in the open today, in order to ensure that [the] political temperature does not go up because there's a lot of anxiety in the country," he said.
Local media reports that the ministers who lost their seats all had all run on the ticket of Mr Kibaki's Party of National Unity, a broad-based coalition.
At an overnight news conference, the ECK head, Samuel Kivuito, said there had been delays in voting and counting, and the process of compiling results was going slowly.
Some say the huge numbers overwhelmed the authorities. The queue of voters stretched for more than a kilometre outside some polling stations.
Voting was extended in areas where polls opened several hours late, notably in the Nairobi slum of Kibera: Mr Odinga's constituency.
Mr Odinga, who fell out with Mr Kibaki shortly after helping him to win the presidency in 2002, alleged fraud before the polls opened.
Mr Odinga was at first not allowed to vote on the grounds that his name was not on the voters' roll, though he did cast his ballot later in the day.
The president has denied involvement in any election fraud.
Correspondents say that in Kenya's previous elections, the outcome has been obvious before polling, or at least there has been a strong favourite.
President Kibaki hopes his economic record will secure a second term.
Mr Kibaki's critics accuse him of failing to keep his promise to tackle corruption.
There were six other candidates in the presidential elections besides Mr Kibaki and Mr Odinga.
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