NAIROBI, June 9 (Reuters) - In Kenya, they name babies after him and quaff "Senator" brand beer in his honour. Global TV networks camp outside his grandmother's rural home.
In Uganda, a town has renamed a street "Obama Boulevard".
And in Nigeria, militants even called a brief ceasefire in praise of the U.S. Democratic presidential nominee.
"Obama-mania" has been sweeping through Africa all year, but the euphoria hit new heights when he clinched his party's ticket last week to run for the U.S. presidency in November.
The positive symbolism of seeing a man with an African father nearing the world's most powerful position is obvious.
"The fact today whites can choose a black man as their candidate is a mental revolution in the United States," Senegal's President Abdoulaye Wade noted.
But beyond the feel-good factor, there are doubts as to whether Barack Obama could bring tangible benefits to Africa if he enters the White House.
Millions on the world's poorest continent hope the Illinois senator can deliver on aid, trade and heavyweight political support. But many are also warning against over-expectations.
For a start -- obviously -- he may not actually win.
"All this celebration could be premature ... his presidency is not a done deal yet," Kenya's Daily Nation newspaper reminded a nation exulting at his nomination.
Obama's late father was Kenyan, and on a trip here two years ago he was feted like a rock star. But apart from visits to his ancestral roots, Obama does not have a particularly strong track record of interest in Africa, analysts say.
"PREPARE TO BE DISAPPOINTED"
So being black and having a Kenyan dad are no guarantee he will hoist Africa up Washington's list of global priorities.
Like others, Ugandan columnist Timothy Kalyegira took note of Obama's decision to make his first post-victory speech to a pro-Israel lobby group rather than "adoring" black Americans.
That, he said, "should open the eyes of those who imagine that Obama is going to advance black interests or those of Africa ... Prepare to be greatly disappointed by Obama."
Few realistically expect Africa to compete successfully with issues like Iraq, China and the Middle East be it Obama, or Republican candidate John McCain, who takes the White House.
Richard Dowden, director of the London-based Royal African Society, predicted "business as usual" from Washington towards Africa even if Obama wins. Recent policy on Africa has been dominated by counter-terrorism, oil supply and humanitarian aid.
"Obama's rise has obviously given Africa more self-confidence, which is great," Dowden said. "But it is not as if he has any particular knowledge of Africa or great contacts.
"Remember too that he backed the Farm Bill which was very damaging to African trade interests, whereas McCain did not."
And while Africans are used to leaders who wield huge individual clout in their nations, a U.S. president has plenty of checks and balances despite leading the global superpower.
"Because of the history of Big-Manism in Africa, Africans think of presidents as omnipotent, omniscient and omnipresent ... In contrast, the American presidency is a highly circumscribed office," Kenyan columnist Makau Mutua said.
"Obama may change the pigmentation and racial identity of the person of the president. But does that mean anything? ... Africans and black people the world over must curb their enthusiasm about what an Obama presidency can do for them."
CLINTON VS BUSH
Obama's fellow Democrat Bill Clinton was massively backed by black voters and even dubbed by some an honorary "African-American", but his legacy to Africa is ambiguous.
Some might say it is most remembered for the failure to stop Rwanda's genocide, and an ignominious military exit from Somalia.
Despite being less popular globally, President George W. Bush received some acclaim on his recent trip to Africa, particularly for U.S. funding to fight AIDS.
"Let it not be forgotten that it is he (Bush) who appointed the first black secretary of state. It is also he who has been putting pressure on dictators in the world, especially in Africa and Asia," Kenyan resident Harrison Ikunda wrote in one of a stream of letters to newspapers debating the Obama phenomenon.
"A warning shot to Africa: Obama may be good for Africa, but first and foremost he is an American. He is unlikely to jeopardise American interests to pursue others."
While the debate is almost always cast in terms of what Obama might do for Africa, a major investment push by China and others on the continent has Washington worried.
And there, resource-rich Africa has influence.
"Africa is receiving concerted interest from other powers, including China, India, and Japan," said Mark Schroeder, of U.S. think-tank Stratfor. "Africa will not give a free pass to Obama, despite the heritage and symbolism, and risk losing out on billions of dollars worth of competing investments."
Despite such caveats, nothing can deny Africans a moment of glory in Obama successes so far.
From his grandmother's village in western Kenya to the fan clubs sprouting all over Africa, the cheers are loud and long.
"We are elated, he's one of us!" cousin Moses Obama told Reuters in another long day of interviews at Kogelo village.
"When he eventually succeeds, his joy will be our joy." (Additional reporting by Diadie Ba in Dakar, Daniel Wallis, Donna Omulo and Jack Kimball in Nairobi; Editing by Daniel Wallis and Matthew Tostevin)
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