Counting votes in Kenya's tight presidential race could stretch into Saturday, according to election officials who say the results so far are too close to call.

On Thursday Kenyans lined up for kilometres to cast their ballots in some areas, a sign observers say shows people are increasingly confident their votes count. 

Riot police protect ballot boxes after violence broke out over reported election fraud in Ngong, just outside Nairobi, on Friday, but observers are generally calling the election fair.
(Karel Prinsloo/Associated Press)

They voted for national and local legislators, but the main race is between President Mwai Kibaki and his former ally, Raila Odinga.

Some local media reported partial results Friday showing opposition challenger Odinga pulling ahead, while a separate exit poll put Kibaki in the lead. Kibaki, meanwhile, urged Kenyans to wait for the official results.

"We wish to remind all Kenyans that the responsibility for counting the votes and for announcing the election results rests solely with ECK [Electoral Commission of Kenya]," he said in a statement.

Kenyans suffered much violence in the run-up to the election, with hundreds killed, and several diplomats have expressed concern that a narrow victory on either side could lead to rioting by those who do not accept or trust the results. But Thursday's process was generally orderly, and no major disruptions were reported.

"It might be safe to say at this early stage that the polling was a success," the Daily Nation newspaper said in a Friday editorial.
  
Kibaki won by a landslide victory in 2002, ending 24 years in power by Daniel arap Moi, who was constitutionally barred from extending his term. Moi's blanket use of patronage resulted in crippling mismanagement and a culture of corruption that plunged Kenya into an economic crisis.

Kibaki, 76, came to power on pledges to reduce corruption and improve the economy. He succeeded with the economy, and the country now basks in a growth rate that is among the highest in Africa. But Kibaki's anti-graft campaign has largely been seen as a failure, and the country still struggles with tribalism and poverty.

Odinga, a 62-year-old former political prisoner under Moi, cast himself as an agent of change and a champion of the poor. But he has been accused of failing to do enough to help his constituents during 15 years as a lawmaker.

With files from the Associated Press