While trumpets were blaring and Mardi Gras beads were being tossed after the Saints' monumental Super Bowl victory, revelers were asking "who dat?" But urban politics had already given its latest answer.

Earlier this month, voters in the Big Easy chose Mitch Landrieu as mayor, making him the first white mayor of the city since his father held the office more than 30 years prior. But the election signifies something very different: a change in the voting tastes in cities with large black populations.

Since the assassination of Martin Luther King Jr., majority African American constituencies have been increasingly creating voting blocs that almost exclusively send black candidates to public offices, city councils, state legislatures and even the U.S. House of Representatives. And when they didn't send a brother or sister to the House, the rep needed to at least connote his love of barbecue and Ray Charles' music.

But since the notable 95 percent black backing of President Barack Obama in densely black areas, people who would have never gotten a black vote a generation ago have been winning elections or at least coming very close.

The first clue was in New Orleans in 2008, when moderate Republican Joseph Cao, a Vietnamese American, defeated nine-term Democrat William Jefferson, who was eventually imprisoned on corruption charges. Louisiana's 2nd Congressional District is an area that Jefferson had on lock for years. Any challenge to him made almost no sense.

But skepticism about Jefferson's effectiveness, the corruption charges and Hurricane Katrina changed the voting demographic there, leaving the stream wide open for Cao to take the seat.

The next year, in Atlanta, one of the most heated mayoral races in years nearly put city councilwoman Mary Norwood in City Hall. She received 46 percent of the vote, more than any other candidate, but the rules there state that if nobody gets more than 50 percent of the vote, a runoff must take place, which happened on Dec. 1, which resulted in her opponent, Kasim Reed, taking office.

What is striking is that Atlanta is 56 percent black, perhaps enough to have easily given Reed the win, but black voters there did not give him strong support. It should also be noted that Atlanta has lost as much as 15 percent of its black population since the mid-1970s.

Chicago is probably the most noticeable city with a significant black population with a white mayor (Richard M. Daley). He defeated Eugene Sawyer, who replaced Harold M. Washington in 1989. Blacks are clearly keeping Daley in office as much as whites are.

But back in New Orleans, Landrieu's election possibly represents less of a demographic shift and more a change in what African Americans will vote for. The '70s and '80s represented a time when blacks sought black faces to represent them in government. Perhaps now, they are seeking the strongest representation, looking for more bang for their buck.

If black Americans do not feel beholden to vote for a municipal or legislative candidate just because he or she is black, then it won't be long before any particular party will have to stop taking our votes for granted. Maybe that's a good thing, maybe that's what post-racial really means.