NAIROBI, Kenya — Kenyan President Uhuru Kenyatta on Wednesday led challenger Raila Odinga by a significant margin in partial election results, but the opposition said the counting process was flawed and disputed the tally.

The website of Kenya’s election commission showed Kenyatta with just over 55 percent and opposition leader Odinga with nearly 44 percent after votes were counted from more than two-thirds of the 40,833 polling stations. However, the commission did not release information about which constituencies had been counted, so it was unclear whether Kenyatta strongholds or opposition centers, or some combination, had yet to be tallied from Tuesday's vote.

That prompted sharp criticism from Odinga, who also ran against Kenyatta in the 2013 vote and unsuccessfully challenged the results in court with allegations of vote-tampering. The longtime opposition figure also ran in the 2007 vote, which was followed by violence fueled by ethnic divisions that killed more than 1,000 people.

“A clean credible process would by now have a dashboard showing all tallies from all constituencies to add to a sum total so that the country can know which part of the country has been counted and what the votes are,” Odinga said in a statement Wednesday.

“The system has failed,” Odinga said.

He added that the election commission “has just said that no parties have disputed the results. How do parties dispute results which they do not even know their origins?”

Election officials acknowledged the opposition objection, but defended their actions.

“We believe that by displaying results, we have been doing well to enhance transparency and accountability in the electoral process, consistent with the commitment the commission has made to the Kenya people,” said commissioner Consalata Bucha Nkatha Maina, vice chairwoman of the election commission.

Authorities hope to avoid the post-election violence of a decade ago when ethnic divisions fueled unrest that killed more than 1,000 people.

By law, election officials have up to a week to announce results, though many analysts believe the outcome of the presidential race will be declared far sooner, possibly within one or two days.

Because Kenya is an African leader, its election is a closely watched event across the continent and beyond. Its diversity, symbolized by the gulf between its so-called Silicon Savannah ambitions for a booming tech industry and the poverty and lack of services found in shantytowns or remote rural areas, as well as its complex ethnic patchwork, mirror the potential for advancement, and the obstacles to it, across the wider region.

“If the elections are not fair, if there was rigging, people will definitely go to the streets,” said Sophia Ajwang, a 29-year-old student in Kisumu city.