The key to success in US presidential politics is to be the right person in the right place at the right time. That, in a nutshell, explains why a first-term Illinois senator is now the clear favourite to win the 2008 Democratic nomination, and quite possibly the White House as well.
No one doubted Barack Obama's huge political gifts when he first publicly toyed with the idea of a presidential run in late 2006. But many wondered, wouldn't it be better to wait until he had gained more experience?
In an ideal world, yes. But no US presidential year is like another. The Obama qualities are perfectly suited for this particular moment.
A better and more popular president than George Bush would have created an entirely different environment for his succession. Instead, Mr Bush's miserable failure has generated a national yearning for a new beginning, with which the Obama message of hope and change resonates perfectly.
As for experience, the Bush adminstration was brimming with it, only to commit the monumental blunder of invading Iraq. America wants a feel-good story, and Mr Obama provides one. Were the public mood less sour, a feel-good might not matter.
This explains his trump card that Hillary Clinton and other candidates simply haven't been able to match – an ability to inspire people to vote in unprecedented numbers. In a normal year Ms Clinton's voting support would be more than respectable. Not in 2008.
Mr Obama's sweep of Tuesday's "Potomac primary" was astounding for its size and the breadth of his support. For the reason look no further than the turnout; in Virginia alone almost one million, compared to under 400,000 in the Democratic primary of 2004.
For Ms Clinton everything now depends on Ohio and Texas, two "mega-states" that vote next, on 4 March. A split is not enough, she almost certainly will need to win both. Yet the momentum is with Mr Obama. Her leads in both states have eroded. He has more money than she does, and the electoral calendar favours him. When he has time to get voters to know him, he tends to prevail. There are almost three weeks until Texas and Ohio, a political eternity.
But the gap also allows Ms Clinton time to regroup. Mr Obama's youth and race make him a tricky target. But the Clinton campaign is nothing if not battle-hardened, and will not shrink from stepping up its attacks. Yesterday it aired its first (albeit relatively mild) negative ad against him.
Three weeks too is more than enough time for a huge gaffe from Mr Obama, or for the media which have thus far treated him with kid gloves, to unearth some damaging revelation from his past. Would the unsullied, almost virginal aura that constitutes much of his appeal withstand serious mud thrown in its direction?
For the moment, however, all is set fairer than anyone would have believed six months ago. Mr Obama is simply the right person in the right place at the right time.
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