The presidential campaign has once again pivoted to the enduring — if rather pointless — argument about which ticket offers the most "authentically American" slate of candidates.

Last night's debate between Barack Obama and John McCain stayed away from biography and focused firmly on policy.

But this issue of who is more authentically American was given fresh steam a few days earlier by Republican vice-presidential candidate Sarah Palin, who, gosh darn it, returned over and again to her bedrock, rural American roots in her debate with Sen. Joe Biden.

What we were hearing was, in a way, Round 2 of the conversation that ebbed and flowed earlier in the campaign over Obama's authenticity and "American-ness."

For instance, there was the strategy memo by Hillary Clinton strategist Mark Penn, who suggested a profitable line of attack in a private memo when he noted:

"All those articles about (Obama's) boyhood in Indonesia and his life in Hawai'i are geared toward showing his background is diverse, multicultural, and putting that in a new light … expose a very strong weakness for (Obama) — his roots to basic American values and culture are at best limited …"

To her credit, Clinton didn't use this approach, at least not overtly. But it was and remains a subtext among those who believe Obama is not qualified to be president. That was equally the subtext in Palin's stress on her very ordinary, small-town American-ness. "To the voters: I'm like you; they're not."

On Friday, Timothy Noah had an amusing column online at www.slate.com/id/2201548 which explored this question of whether small-town rural Alaska is more "authentically American" than exotic Hawai'i.

In truth, Noah concludes, if demographics matter, then Hawai'i is more like America than Palin's rural Alaskan hometown. After all, most Americans live in cities, not in the countryside. And Hawai'i, particularly Honolulu, is distinctly urban.

It's interesting that Palin seems eager to make her rural Alaskan roots the key to her authenticity while Obama clearly is not eager to make the same claim for his Hawai'i roots.

But who can blame him when you look at things like the Penn memo, which suggests there is a way to take what should be one of Obama's greatest strengths, his roots in multicultural Hawai'i, and turn it into a weakness.

This all illustrates that in politics, as much as we would like campaigns to center on issues and policies, it often comes down to imagery and biography.

That's a reality every candidate has to deal with.

Jerry Burris is the author, with Stu Glauberman, of the new book: "The Dream Begins: How Hawaii Shaped Barack Obama" (Watermark Press) His column appears Wednesdays. See his blog at www.blogs.honoluluadvertiser.com. Reach him at jrryburris@yahoo.com.

Jerry Burris' column appears Wednesdays in this space. See his blog at blogs.honoluluadvertiser.com/akamaipolitics. Reach him at jrryburris@yahoo.com.