Larry Sabato, a political scientist at the University of Virginia who has studied African American precincts, said he had occasionally seen 100 percent of the vote go for the Democratic candidate. Chicago and Atlanta each had precincts that registered no votes for Republican Sen. John McCain in 2008.
"I'd be surprised if there weren't a handful of precincts that didn't cast a vote for Romney," he said. But the number of zero precincts in Philadelphia deserves examination, Sabato added.
"Not a single vote for Romney or even an error? That's worth looking into," he said.
Sabato's paranoia is undermined by the fact ""in 2008, McCain got zero votes in 57 Philadelphia voting divisions."