If he loses, he'll make history as the only incumbent Kenyan president not to win re-election. Independent Electoral and Boundaries Commission (IEBC) spokesman Andrew Limo said turnout "looks huge" so far and as votes are cast at the more than 40,000 ...
"I have been here for around two hours," one man standing in line at a polling booth in Busia County on the border with Uganda told CNN affiliate NTV. "I came at six in the morning to exercise my democratic right and bring change to this country."Raila Odinga, who's running for president for the fourth time, served as prime minister between 2008 and 2013. As the candidate for the National Super Alliance party, he is one of eight presidential candidates and the incumbent's main challenger.Kenyatta, who leads the Jubilee Alliance and is seeking a second five-year term, is the nation's youngest president at 55. If he loses, he'll make history as the only incumbent Kenyan president not to win re-election.Independent Electoral and Boundaries Commission (IEBC) spokesman Andrew Limo said turnout "looks huge" so far and as votes are cast at the more than 40,000 polling stations.
Limo acknowledged claims of malfunctioning voting machines, which have circulated online, saying there have been "three or four cases of malfunction where the system needed restarting" but added that for the most part things have "gone well."
"Little glitches here and there will be fixed as they occur," he said.
Kenyans wait to cast their ballot at a polling station in the Rift Valley town of Eldoret on August 8.
The two top contenders are from political dynasties that date back decades.
Kenyan President Uhuru Kenyatta is the son of the nation's first president.
The president's father, Jomo Kenyatta, was Kenya's first president while Odinga's father, Jaramogi Odinga, served as his vice president. The pair led the nation after it gained independence from Britain in 1963.
This is not the first time the sons have run against each other.
Five years ago, Odinga contested the outcome of the election at the Supreme Court after Kenyatta narrowly defeated him. He accused his party of electoral fraud, but the court ruled against him.
Presidential hopeful Raila Odinga is the son of the first Kenyan vice president.
Fast-forward to this year, and Odinga, 72, has accused Kenyatta of attempting to rig the election. Kenyatta has in turn said Odinga is attempting to divide the country.
To win the election outright, a candidate must gain 50% of the votes, plus one -- as well as at least 25% of the votes in half of Kenya's 47 counties.
If no winner is declared, the election will go to a runoff, which would be a first in Kenya's history.
More than 11,000 polling stations -- around a quarter of the total -- are without decent mobile coverage, meaning returning officers have to use satellite phones and other means to transmit results.
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A peaceful vote is crucial to maintaining regional and economic stability.
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As the largest economy in East Africa, Kenya is an important trade route into the rest of the continent. It provides an important buffer of stability in a region that includes the struggling Somali government, and the politically-tense Sudan and South Sudan.
Kenya is also a major US ally in the war against Islamist militants in Somalia, where its troops have been fighting Al-Shabaab fighters for years. It's also home to the African headquarters of several international aid organizations, including the United Nations.
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Both candidates have campaigned largely on promises of improving the economy and fighting corruption, a major issue in the government.
Kenyatta has promised to create 1.3 million jobs, reduce the cost of living and address economic inequalities. Odinga has vowed to fight corruption, create jobs for young people and set up programs to improve food security.
The youth vote is highly coveted. Young people between ages 18 and 35 make up 51% of the country's 19.6 million registered voters.
Related: Will Kenya's young people swing the election?
Kenya's last election in 2013 was mainly peaceful, but a decade ago, the country plunged into widespread violence in the aftermath of the 2007 vote.
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More than 1,000 people were killed in months of bloodshed following the 2007 election after Odinga -- defeated by the then-President Mwai Kibaki -- claimed the vote was rigged.
Opposing protesters loyal to each leader took to the streets, and protests escalated into bloody violence, fueled by decades of economic frustration and ethnic rivalry.
The killing of a senior election official days before the election sparked tensions last week. Chris Msando was head of information technology for Kenya's Integrated Electoral Management System. While his department was responsible for voter identification and result transmission technology for the elections, it's unclear whether his killing was related to the election.
Leading up to the poll, wary residents stocked up on food and water amid fears of a return to violence. But others expressed hope the election will be peaceful.
"We learned our lesson in 2007 on how easy it is to tear our nation apart," said Jane Wambugu, who lives in Nairobi. "I've bought enough food supplies for two weeks -- flour, sugar, beans, everything. But I hope to God I won't need them."
africa,Kenyans vote in hotly contested presidential election - CNN