The politicians will deny it, but the referendum is no longer about the constitution. It is the starting gun in the race for the 2012 general election.
For President Kibaki, there is also a desire to leave a legacy.
He is not eligible for re-election when his second term expires.
But as the last referendum on constitutional change in 2005 showed – a vote won by the "No" campaign – political ambitions will always overshadow the careful consideration of the country's best interests. The "No" campaign's victory emboldened an anti-government faction, led by Raila Odinga, who is now Prime Minister, to form the Orange Democratic Movement (ODM) and contest the 2007 election under that banner.
Odinga seized the moment and used the result as a test run for the country's top seat. So when you hear Kenya's leaders claim that the referendum is not about succession, it's hard not to feel that they are incorrigible liars.
Kibaki, at least, has been frank about his interest in leaving the arena on a high. He doesn't seem even to care what the constitution contains: all he wants to make sure is that he goes down in the annals of history as the president who got it done. But it won't be able to hide the fact that, during his tenure, Kenya sank into civil war and turmoil.
It is well known, meanwhile, that Odinga wants to ascend to the presidency and conquer the position that his father – the doyen of opposition politics, Jaramogi Odinga – could not.
Raila and his handlers believe that victory in the referendum could be seen as an endorsement that will give him real momentum for the top job. He will be able to claim, during the campaign, that he was responsible – along with Kibaki – for mobilising the country to vote.
But none of that is guaranteed. A "Yes" vote could equally lead Kibaki to decide that with his place in history assured, and with no further need of Raila's support, he could endorse another candidate – a move that could lead the Higher Education Minister, William Ruto, to pay back Raila, who beat him to the ODM nomination, by going into alliance with anyone but him.
As the vote finally approaches, none of the consequences are clear cut. The only certainty is that the country's constitutional future will play second fiddle to personal rivalries, deceit, and political vengeance.
The author is a journalist at The Standard newspaper in Kenya and recipient of this year's David Astor award