"You can hear about an issue in traditional media and be outraged. But in social media you have immediate feedback of how much your friends are outraged," Castillo said. "It's just a huge facet of social media that affects that mobilization. It's sort of the same thing as word of mouth, but just at a lightning speed."
Recent research by the Pew Research Center's Internet & American Life Project shows why this case might particularly resonate for the black Internet audience.
Aaron Smith, a senior researcher for Pew Internet, said a study updated last month shows that 15 percent of all Internet users nationally use Twitter, including 8 percent on a typical day.
White users are generally in line with the national average with 12 percent using the service or 7 percent on a typical day.
By contrast, black Internet users have very high rates of Twitter usage, with more than a quarter using Twitter overall and 13 percent using Twitter on a typical day.
"It's a bit different data than we've seen historically," Smith said. "For a long time, it was always a digital divide story. But with social (media) we're finding the black community on par with or ahead of their white counterparts with usage."
Associated Press writer Suzette Laboy in Sanford contributed to this report.
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