Campaigns can be messy things. Last Tuesday, in a non-descript hotel room in Washington, Barack Obama’s microphone wasn’t working. It gave out a low, yet ear-splitting drone that never quite went away. Cameramen at the back of the room kept yelling at young, overwhelmed staffers to get out of their sightlines.

And Obama’s speech itself – on tax policy – was read from the Autocue as if he were reading it for the first time, stumbling over even the name of his wife. The effortless grace of that spellbinding 2004 convention speech seemed from another era.

The exhilaration of his campaign announcement in the cold sparkling Illinois winter was over. And as he droned on about tax breaks for the working poor, I found myself more interested in the crowd than the speaker.

But as I left, it also occurred to me that I’d just been bored by a black politician on tax policy. In fact we all had. And yet such is the quiet transformation that Obama has already wrought on American politics that nobody even noticed.

The days in which African-American politics were defined by Jesse Jackson and Al Sharpton, or, even worse, Louis Farrakhan, are over. And as if to underline this achievement, Jack-son took the opportunity to condemn Obama the next day for “acting white” because he wasn’t articulating sufficient outrage at a recent civil rights controversy in the South.

The conventional wisdom about Obama is that his campaign is flailing before the relentless bulldozer of the Clinton machine. There is less to this, I’d say, than meets the eye. His campaign began with astonishing momentum – a bestselling book, media blitz, a sudden spurt in the polls, followed by a fundraising effort that beat the prodigious favourite, Hillary Clinton. Throughout 2006 and the first quarter of 2007, Obama’s national trend line in the polls was a relentless ascent, compared with Clinton’s ever-so-slight glide down. But some time this spring, he stalled and she rallied.

His support hasn’t slumped much since then; it has simply trodden water at about 20%. Clinton, in contrast, was at 38% in 2005, bottomed out at about 35% this spring and, after some superb debate performances, is now about 39%. Yes, she has twice the national polling of Obama. But in the key early races, the polling is much closer. Obama is clearly hoping that his deep pockets, very large donor base – a quarter of a million people have now donated to his campaign – and appeal to independents will keep him in the game long enough to pull off an early surprise.

Wishful thinking? The Obama campaign suspects Hillary is ahead because Hillary is ahead. She has global name recognition and deep loyalty among the most partisan and loyal Democrats. She is essentially using the same tactics that George W Bush did in 2000 – trying to amass so much money and so many endorsements that a reputation for inevitability leads to actual inevitability.

Obama, in contrast, is trying the John McCain strategy of 2000 – carve out a reputation for independence and leverage an early surprise into enough momentum to take down the frontrunner. Unlike McCain, a Republican candidate again for 2008, Obama has enough money to survive next January, and then some.

If fellow Democrat John Edwards drops out in the early stages, his 10% could go to Obama. If Obama seems a viable candidate in South Carolina, that primary’s substantial black vote could break at the last minute for the black man in the race. That’s the game plan anyway. It’s the only game plan that makes sense for an insurgent candidacy taking on an establishment favourite.

The war is the great variable. The past two weeks have led to a surprising dynamic. By backing a continuation of the surge, by declaring the strategy a success, and by killing even the most minimal attempt to restrain the president, the Republicans have wedded themselves indelibly to a war whose outcome they cannot control. McCain’s new slogan is “No surrender”, an atavistic framing of the complex debate about Iraq to appeal to the basest of Republican instincts.

It has served him well with his party’s base. Clinton and Obama, in contrast, have been issuing antiwar statements that are close to indistinguishable. Obama’s advantage is that, unlike Clinton, he opposed the war from the start. With the Democratic base incandescent with frustration at their congressional leadership’s inability to change the president’s policy, Obama has a chance to pick up support if the war turns sour again.

Under these conditions, you’d expect Clinton to be toning down the rhetoric and Obama ratcheting it up. But the opposite has happened. Clinton described Vice-President Dick Cheney last week as “Darth Vader” in front of a Democratic crowd. They loved it. Obama unveiled his first Iowa ad for Democratic activists that included this sentence: “In 20 years of public service, I’ve brought Democrats and Republicans together to solve problems that touch the lives of everyday people.” This message is not just for public consumption. In Democratic-only settings he often proudly cites his support from Republicans. In a polarised climate, where Rudy Giuliani is already lambasting Hillary and itching for a fight, Obama is sticking to a disciplined message of reconciliation, unity, responsibility.

Is this a mistake? Whoever won a Democratic primary by insisting on being open to Republicans? That is the risk Obama is taking. But when you observe and listen closely, you see this is what he actually means.

He detects an enormous weariness among Americans about their internal divisions in a time of war, overlaid by the anger and divisions that have deepened and widened under the Bush presidency. He suspects that if he can get past Clinton’s aura of inevitability, Democrats will realise he has a much better chance of winning a real national majority in the general election than Clinton does. Clinton polarises the way Bush polarises. She can hope for a Karl Rove-style 51% majority in a deeply divided country. He’s aiming for 55%.

Clinton, in other words, represents payback for the Democrats and liberals after the Bush era, just as Giuliani is emerging as the inheritor of the Bush legacy of divide and rule. Right now, Obama remains to the side, offering Americans something else: not payback, but a new page.

Neither black nor white, neither atheist nor born-again, a candidate who favours withdrawal from Iraq but an offensive against Al-Qaeda in Pakistan, a progressive offering the working poor a tax cut, his bet is that, in the end, America wants to come together again. The unanswerable question is whether America really does.

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