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By Daniel Wallis and Katie Nguyen
NAIROBI, Dec 28 (Reuters) - Kenya's opposition challenger Raila Odinga took the lead on Friday in the race to govern east Africa's biggest economy, media tallies showed, while activists voiced fears over delayed official results.
If the entrepreneur and son of a nationalist hero does win, President Mwai Kibaki would become the first of Kenya's three post-independence leaders to be ousted by the ballot box.
Three local TV stations aired unofficial, partial results showing Odinga holding a commanding lead. KTN had him on 2.98 million votes versus Kibaki's 2.02 million. That represented about half the 8-10 million ballots thought to have been cast.
But by 5 p.m. (1330 GMT), the Electoral Commission of Kenya (ECK) had only released results from 28 of the country's 210 constituencies, with Kibaki leading by 693,195 votes to 517,800.
The delays at the ECK raised concerns among grassroots activists and Odinga's opposition Orange Democratic Movement.
"In this era of technology, it is surprising that ECK seems to be moving at a snail's pace in satisfying public hunger for information," civil society groups said in a statement.
"ECK must do better ... otherwise a situation will be created where sections of Kenyans will dispute the results."
Scenting victory, Odinga's supporters said they feared the delays meant the government was plotting to rig the results.
"Is this a strategy to impose a rejected regime on the people?" asked opposition official Joseph Nyaga. He accused the ECK of withholding results from the key Central Province "pending instructions from senior government officials".
The ECK denied any interference but also lamented the delays, which it said could extend the process into Saturday.
"If results were announced on the media two hours ago, the returning officer has no excuse for not getting them to us," ECK Commissioner Jack Tumwa said. "The country is getting restless."
'ENVY OF AFRICA'
Diplomats say the poll was only the second truly democratic one in a country that votes largely on ethnic and geographic lines and spent 39 years under single-party rule until Kibaki's landslide victory in 2002.
The turnout looked to be the highest since multi-party politics was reintroduced in 1992, and observers said voting had gone smoothly, despite sporadic violence and allegations of ballot fraud by both sides.
"The ECK has run elections with efficiency and independence that should be the envy of the rest of Africa," the local Daily Nation newspaper said in an editorial.
In one incident on Friday, police fired in the air to disperse youths accusing Education Minister George Saitoti, a Kibaki ally and former vice-president, of trying to rig the parliamentary vote in Kajiado, south of Nairobi.
Numerous well-known faces lost their seats in the polls, including Kenya's Nobel laureate Wangari Maathai, the vice-president, and 10 government ministers, local media said.
Kibaki, 76, wants a second five-year term before retiring to his highland tea farm after a political career that has spanned Kenya's post-independence history.
With a record of average economic growth of 5 percent, he has the support of his Kikuyu tribe, Kenya's largest and most economically powerful, but trailed narrowly in pre-vote polls.
Odinga, a 62-year-old former political prisoner educated in communist East Germany, wants to be the first in his Luo tribe to take the country's top job.
That was the unrealised dream of his father, Kenya's first vice-president, Jaramogi Oginga Odinga, whose falling out with founding president Jomo Kenyatta seeded the Luo-Kikuyu rivalry.
Should he win, Odinga will have to enlist Kikuyu support and allay business fears that he is a left-wing radical. (Additional reporting by Duncan Miriri, George Obulutsa, Joseph Sudah, Wangui Kanina, Andrew Cawthorne, Bryson Hull, Helen Nyambura-Mwaura and Nicolo Gnecchi; Editing by Giles Elgood)