If Barack Obama were a state, he'd be California, said Maria Shriver as she endorsed Obama last weekend.

But what if Barack Obama were white? What if Hillary Clinton were a man? What if John McCain were a woman? What if Mitt Romney were a black female Baptist?

The "what if" question is useful across the board as voters wrestle with identity politics. I don't mean to be flippant, but rather to suggest that we are more biased than we admit and that just possibly our bias interferes with judgment.

We keep hearing that Obama's candidacy isn't about race and Clinton's isn't about gender. But clearly this presidential campaign season is about both. It is also about age and religion, in the cases of McCain and Romney, respectively.

Sometimes it isn't possible to separate content from these prisms of perception, as this exercise demonstrates. But removing the lens of personal identity can be instructive by forcing us to focus more intently on substance.

Despite key endorsements from the African-American community, the Obama phenomenon primarily has been about white America, as black author Shelby Steele recently noted.

"There is this (white) need, this driving hunger, to somehow get this race thing resolved, to redeem the country, to get beyond it. ... That's (the) phenomenon," he said in an interview with the Hoover Institution's Peter Robinson.

Voting for Obama because he's a black man may be defensible for all those reasons. He is also capable of inspiring hope and unity, no small things, and seems to take a thoughtful approach to issues. But would a white Obama -- and the most liberal member of the Senate, according to National Journal -- be acceptable as the leader of the free world?

If Hillary Clinton were a man, she probably wouldn't be running for office because she wouldn't have been married to Bill Clinton, which means she probably also wouldn't be a U.S. senator. It's almost impossible to separate Hillary Clinton's candidacy from her marital status and thus her gender.

It may be that Americans want to see a woman in the Oval Office enough to overlook what is an unremarkable Senate record. They may well figure that she's smart enough and note that Clinton consistently has surpassed her male challengers in debate.

Liberals may find her standing as the 16th-most-liberal senator acceptable and bet that she will keep her word to withdraw troops from Iraq no matter what generals on the ground say. Continued...