From WNYC in New York, this is NPR's On the Media.

I'm Bob Garfield.

And I'm Brooke Gladstone.

Who is Barack Obama?

That's a question asked repeatedly in the waning days of this election season by the McCain campaign.

Millions have been watching Obama, studying Obama, for nigh on to 20 months.

But the McCain campaign says that we don't know him, and that makes him too risky for America.

Vincent Williams writes the social studies column for the Baltimore City paper,

and he's been writing about what many claim is the subtext for this charge of

unknowability, that Obama is unknowable to some Americans because Obama is black.

Vince, welcome to the show.

Thank you. Thank you for having me.

So what do you think these ads are trying to do?

Well, I think they're trying to really feed into this notion that even though Barack Obama has been on the public stage generously two years, certainly since 2004, that there's still something unknown about him.

How do you think race plays into this idea of Obama as the other?

Well, I think oftentimes when you're addressing issues of race,

unknown is just code for other,

so that no matter how much information you may have about a black person, they are still

unknown.

Conversely, Sarah Palin, a couple of months ago when she was introduced almost immediately,

Code was being put forth that she's one of us, she's a hockey mom, She's regular. When we really knew not much about her. Even at this point, I don't know how much we know about Sarah Palin. And frankly, I don't know how much it matters to people.

One thing we do know about Palin is that she's been the pit bull with lipstick spreading far and wide this notion that Obama is not like us.

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