A WOMAN stood clutching her seven-month-old baby near the front of a long queue to see the fresh face of American politics — a face that belongs to Senator Barack Obama, and which just happens to be black.

Joanna Williams had got her children out of bed at 4am, driven them to Denver, then waited almost six hours to shake Mr Obama’s hand and have him sign his book for her.

She is white and wanted to speak about her husband, a black man stationed with the military hundreds of miles away in Louisiana and soon to be deployed to Iraq, to tell Mr Obama “how these are real people, why they are not disposable”. Mr Obama spent a little more time with Ms Williams than with the 400 others in the queue on Tuesday, waving away aides who wished to keep the line moving. An army wife gets special treatment, he said. He wrote a note on the back of a snapshot, thanking her husband for his service and telling him he had “a beautiful family”.

Outside the bookshop, Ms Williams’s hands were shaking as she said that the Senator should be the next president of the United States. Although such moments are not exceptional in this celebrity-obsessed country, Mr Obama seems to be having an extraordinary effect — not only on voters in these mid-term elections for control of Congress but also on what once seemed cast-iron political certainties.

Mr Obama’s political trajectory is reaching such giddy heights that his thoughts are already turning from the current elections to the presidential race in 2008. In a weekend interview he acknowledged that he had changed his mind and was now thinking about a bid for the White House.

Pundits appear tired of discussing whether Hillary Clinton, long since installed as the frontrunner for the Democratic nomination, can be America’s first woman president. Instead, they are beginning to ask if Mr Obama could be the first black one. Mrs Clinton’s office has remained stony-silent since the weekend about the unexpected emergence of a rival who — unlike her — opposed the Iraq war from the outset.

He is now probably second only to Mrs Clinton’s husband, Bill, as a crowd-pleasing draw for the Democrats in these elections. He made 15 campaign visits last week in a sweep down the East Coast, while this week he is touring the West and South West. He combines his Harvard-honed intelligence with some of the sing-song fluency of an African-American. “Hey, baby”, he says, greeting a woman in a wheelchair at his book-signing in Denver.

It is just two years since he was elected to the Senate and burst on to the national scene with a hugely acclaimed speech at the 2004 Democratic presidential convention that transcended the issue of race. “There’s not a black America and white America and Latino America and Asian America; there’s the United States of America,” he said.

Mr Obama, 45, is the son of a white mother and a Kenyan father. He was largely brought up in Hawaii by his grandparents — apart from a spell with his mother in Indonesia. He has been compared to other high-achieving but, to conservative white Americans, non-threatening black figures such as Oprah Winfrey or Tiger Woods. But his place in US politics is similar to that once occupied by another AfricanAmerican, Colin Powell, who was greeted by adoring crowds when he toured the US in 1996 selling his memoirs while contemplating a run for the presidency.

Mr Obama is combining his whistle-stop campaign tours with signings of his own book, Audacity of Hope. This sets out what he believes are the pragmatic non-ideological “shared values” of America, saying millions have already made peace with their neighbours. “They are there, waiting for Republicans and Democrats to catch up with them.” Critics suspect this is a standard piece of centrist political positioning. But Mr Obama appears desperate not to be judged as just another politician. At a campaign rally in Aurora, Colorado, on Tuesday, he talked about how people were desperate “for someone to have a genuine conversation with them about the challenges facing the nation”. At the time of 9/11 he was told that his name would probably finish his political career — Obama sounded too similar to Osama. It is a measure of how far he has come that on Tuesday John Hickenlooper, the Mayor of Denver, was rhyming the name of Obama with that of the Dalai Lama.

But the Senator remains rightly cautious, saying: “I am new enough on the political scene that I serve as a blank screen on which people of vastly different political stripes project their own views. As such, I am bound to disappoint some, if not all, of them.”

Mr Obama has described receiving this friendly warning from George Bush: “When you get a lot of attention like you’ve been getting, people start gunnin’ for ya. Everybody will be waiting for you to slip — so watch yourself.”

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