Americans love politicians with a compelling life-story, and nobody has a better one than Barack Obama. For all his relative youth and inexperience, the first-term Illinois senator has singularly powerful political attributes.
He embodies the American Dream of overcoming adversity to rise to the top. Like Colin Powell, or Michael Jordan, or Tiger Woods, he is that rare black man about whom Americans do not feel compelled to have a guilty conscience, because he is the product of a marriage between a Kenyan father and a white American mother.
Perhaps most importantly, he is a poster child for the interconnected, global 21st century, and an embodiment of the old-fashioned American idea of the cultural melting pot. He was born in Hawaii, spent part of his childhood in Indonesia, worked hard to make it to elite universities, spent three years as a social organiser on the tough streets of Chicago's South Side, became the first black president of the Harvard Law Review, then threw himself straight back into civil rights work and political advocacy.
His rise to political prominence, graduating from the Illinois state Senate to Capitol Hill in the 2004 election, coincided with the rise of the internet as an organising tool, and the novel approach to grassroots activism pioneered by the Democratic presidential candidate, Howard Dean.
Mr Dean sputtered and failed, but Mr Obama was an overnight sensation. He gave the keynote address at the 2004 Democratic National Convention and upstaged the nominee, John Kerry, with a simple, powerful speech pleading for an end to the divisiveness in American politics and society.
In many ways, a run for the Presidency now would be outrageous. He has been in the Senate barely two years, less than one-third of his term, and has no broad experience of any of the key issues of the moment, starting with national security.
Until now, he has kept his head down in Washington, learning the ropes, plunging himself in committee work and making relatively few public statements.
But celebrity can develop its own momentum, and Senator Obama has spoken in support of dozens of other congressional candidates, and a political action committee he has formed - a rarity for a freshman senator - has raised several million dollars for candidates he endorses.
The big question, by Joe Klein in a Time magazine cover story on Mr Obama, is this: "Would the arrogance implicit in running now, after less than one term in the Senate, undercut his carefully built reputation for judiciousness?"Reuse content