Feature: The Problems of the Post-Racial Politician Operating in an Economic Downturn and Facing an Electorate Still Largely Segregated Along Lines of Class and Skin Color

But the joke fell a little flat that night. Maybe the tune was too obscure. Or maybe it was too hard to hear the lyrics. Or maybe it all came across as a little too defensive.

“We were all like, ‘Okay, we see what you’re doing, but you don’t have to, because we see you for who you are,’” says Chris Johnson, another one of Oliver’s neighbors and the principal of Benjamin Franklin High School.

Who can blame Michael Nutter, though, for not letting it go? Or for bristling at the fact that he was — again — being forced to publicly defend his authenticity as a black man?

As the Mayor puts it to me, in an interview in his office a few weeks after the party, “I’m fully secure and clear about who I am, where I came from and what my life experience has been as an African-American.” Then he adds, “The fact of the matter is, neither you nor anyone else has walked into Ed Rendell’s office and said, ‘Are you white enough?’”

THERE IS NO QUESTION THAT JOHN STREET’S REMARKS were deliberately inflammatory. He made them, he says, to try and gin up an opponent for Nutter in this May’s Democratic primary. But however calculated the comments, they highlight a real problem for Nutter: Support for the Mayor among African-Americans is tepid at best.

Last February, a Pew Charitable Trusts poll found that while 65 percent of white Philadelphians approved of Nutter, only 43 percent of African-Americans did. In August, a Municipoll survey found that 42 percent of black voters thought Nutter was a “good” or “excellent” mayor, compared to 53 percent of whites. More telling was the survey’s finding that in a hypothetical Democratic primary between Nutter and former Republican Sam Katz, only 38 percent of blacks were sure they would vote for the incumbent, with 26 percent claiming they would vote for Katz. When Katz ran against Street in 2003, he earned hardly any black votes — in fact, some post-election analyses put his share at about two percent.