At 68, Raila Odinga, son of Kenya's historical opposition leader, is having his third and likely final stab at Kenya's top job.
The prime minister in the outgoing government, Odinga is a Luo from the western region of Nyanza who likes to say he was "born into politics" and claimed as he voted Monday that he could win outright in the first round of the key election.
Often known by his first name Raila to distinguish him from his father Jaramogi, a prominent post-independence political figure, and his brother Oburu, a member of parliament, he has pursued his political ambitions undeterred by beatings, persecution, exile and several spells in jail.
"He's never finished," said political analyst Mutahi Ngunyi. "Even when everything seems to be going against him, he pulls a rabbit out of his hat and reinvents himself."
In all, Odinga spent almost eight years in jail without trial before briefly being granted political asylum in Norway at the beginning of the 1990s.
His admirers point to the fact that while most Kenyan politicians have their constituency in the town where they were born, Odinga is an exception, being a Nairobi MP. He voted in his constituency on Monday, looking exhausted by months of campaigning.
"Raila is a Luo without question, but he is instinctively and ideologically a genuine nationalist as well," one advisor says.
On the walls of his suite of offices, portraits of himself, his father, and anti-colonial rebel leader Dedan Kimathi jostle for space with the pictures that late conservationist Joy Adamson painted of the different tribes of Kenya.
Odinga was a contender in the 1997 elections where he came third after Daniel arap Moi and Mwai Kibaki, now the outgoing president.
In 2002 he backed Kibaki, who won. In 2007 he ran again, against Kibaki this time, and lost, whereupon his supporters accused Kibaki of having rigged the results.
"Odinga is no doubt motivated by a desire to right what he sees as the injustice of 2007, when he and his supporters think he won the presidential vote," said Daniel Branch, an academic and the author of a book on Kenya's recent history, speaking ahead of Monday's poll.
-- Businessman, not communist --
Long renowned as a firebrand speaker able to galvanise any crowd, Odinga, described as stubborn and sometimes short-tempered, has lost some of his skills as an orator.
Some attribute the change to ill-health that started to take hold in 2006; others say it started when he became prime minister in 2008.
Once he became prime minister, "he could no longer criticise things that were wrong in government without having to do something about them," one of his advisors told AFP.
His energy has also waned -- on at least two occasions recently he was seen almost nodding off during an interview.
However his advisors point out that his pre-election schedule is so gruelling it would exhaust a much younger candidate.
"He's reached an age where he's starting to get tired, and then you have to look at his hectic schedule," said Mwalimu Mati, a prominent civil society figure and anti-corruption campaigner.
Odinga has also dropped some of his more colourful touches such as showing up at rallies in a red Hummer.
Married, Odinga has four children: Fidel, Winnie, Rosemary and Raila Junior.
Odinga grew up an Anglican and later converted to evangelicalism, being baptised in a Nairobi swimming pool by a self-proclaimed prophet in 2009.
He studied engineering in the former east Germany, in Magdeburg and Leipzig, and he called his oldest son Fidel after the Cuban revolutionary.
However, observers say the "socialist" and "communist" labels he was given were more an attempt to discredit him by the Moi regime than an accurate reflection of his leanings.
In a recent interview he reminded AFP that he is a businessman. Somewhat controversially he launched his petroleum import company when he was energy minister in 2001 under Daniel arap Moi.
Odinga has "accumulated" wealth during his time in politics says anti-graft campaigner Mati, "but not on the same scale as Uhuru Kenyatta," his main rival in the race.
If he wins, Odinga told AFP he would prioritise "food, education and jobs" and that he wanted to make Kenya self-sufficient in food production.
He also promised that if elected he would cut the salary of the president and the vice president, but had to admit somewhat weakly he could not remember by what percentage.
In the days of the Cold War, his father Jaramogi's closeness to the Soviet Union worried observers.
Raila, however, is seen largely favourably by the international community, particularly since his main rival Uhuru Kenyatta faces a crimes against humanity trial by the International Criminal Court.