Identity politics once played a decisive role in NYC elections. But the assumption that it always would appeared to have been turned on its head during Tuesday's primary, when Bill Thompson, the only African-American candidate for mayor, did not get a majority of the city's black voters.

It was Bill de Blasio, an Italian from Brooklyn with a multiracial family, who got 80 percent of black majority precincts. 

Mark Winston Griffith, executive director of the non-profit community organizing group The Brooklyn Movement Center, said that's because Thompson failed to "capture the imagination of black voters," and that black voters didn't really find themselves identifying with the candidate.

"Bill de Blasio ... has had strategic relationships with black political operatives and organizers ... progressive forces within the black community spanning decades," Griffith said.

After an unofficial tally, Thompson got 26 percent of the full vote and de Blasio got 40.3 percent. The Board of Election started to count the votes Friday.

To hear Host Amy Eddings' full interview with Mark Winston Griffith, click on the audio above.