I’m just back from a vacation in Portland, Ore., a Blue America town with Obama signs everywhere. It’s the kind of thing that leads one to suppose that Senator Obama’s victory in November is a done deal.

You get the same impression from looking at magazine stands or even just listening to conversations in crowds and elevators. It’s all Obama all the time, while poor John McCain galumphs around geography-challenged and unfocused.

But the urban/collegetown sorts who swoon over Mr. Obama are not most Americans, no matter how many of them surround him in ecstasy when he makes a speech. Nor, of course, are black people anything approaching most of America.

As we are all noticing, Mr. Obama, with his rock star appeal, still has yet to “clinch the deal.” And the tough nuts are older, less educated whites and less affluent than the ones who find Mr. Obama so exciting.

As Steven Warshawsky tells us, in 2004 John Kerry got about half of these people’s vote; i.e., 55% of those with incomes less than $50,000, 47% of those without college degrees. He also got 88% of the black vote. And he lost — despite seeming a done deal among many.

The problem is that all indications are that if the election happened now, Mr. Obama would get somewhat less of this white segment’s vote than Mr. Kerry did. In the primaries, this crowd largely went for Hillary Clinton. It would only take a small percentage of such voters tipping to Mr. McCain for Mr. Obama to lose the election — and even if he got every single black vote, less than 2% of a white shift would cancel out its effect.

Instantly the breathless speculations about the portentousness of this “moment” in American history and commentary on Michelle Obama’s fashion sense would be relics of a bygone era.

Would racism be the culprit? Maybe. The New York Times/CBS poll revealing that one in 20 white voters will not vote for a black candidate for president hardly shows that America is still “all about racism” — it shows how vastly different this nation is than it was 20 years ago. However, the fact remains that this small number could decide a close election like this one.

Or, it would appear that many whites are simply put off by Mr. Obama’s association with the race-baiting theatrics of the Reverend Jeremiah Wright. This need not be racist: all of us are wary of someone who seems like they might hate us.

Then there are those who don’t have a sense of what Mr. Obama is about. These are people who are not especially intrigued by his multicultural biography. They just want to know what he has to offer.

On this topic, we hear this week that the Obama folks are about to put out a book summarizing his policy proposals and reprinting some of his speeches. “A” for effort, but this won’t do it.

For one thing, a book is not the best way to get your message out when the people who need to hear it tend to have a less intimate relationship with the printed page than Obama fans who subscribe to the Atlantic. My wife and I spent part of our vacation in a working-class seaside town, and the used bookstores there were bursting with paperback fiction and children’s books. Nonfiction stuff was on the margins, mostly biographies and books about the movies.

These days even erstwhile pageaholics such as Nicholas Carr, in the Atlantic, are admitting that they barely make it through nonfiction books anymore and are more inclined to scoot around online. Beyond self-help books and other utilitarian tomes, most people do not read nonfiction books and never have.

To avoid John Kerry’s fate, Barack Obama must craft a message designed for oral communication focused on a compact number of points: such as employment, health care, and national security. The message will include, yes, slogans, and soft-pedal long-lined argumentation.

The elegant, carefully reasoned speech in the wake of the Wright scandal only had so much effect. Even press pundits often came away with sound-bite misinterpretations such as “He compared his grandmother to Wright!”

Humans speak in, and recall speech in, utterance packets of about seven words. The Obama folks need to work with that: think “Ending welfare as we know it” and “Mend it, don’t end it.” And not more about hope — the preacherly note goes over great with educated whites and with black people, but has less pull elsewhere.

I sense that Mr. Obama, despite his political savvy, is under the impression that he can get elected on the basis of reflectiveness. But reflectiveness alone has never gotten anyone into the White House, and evidently, charm is not going to get Mr. Obama any further than it already has.

He must start talking turkey, to the crowd who doesn’t think he’s cute for just being himself.

Otherwise, I will start to recall that it was in the working-class Oregon town that we espied a “Nobama” sign.

Mr. McWhorter is a senior fellow at the Manhattan Institute.