It's a name that doesn't come up often. But it's a name that GOP presidential hopeful, Newt Gingrich has been repeatedly bringing up throughout his campaign. Alinsky was an influential community organizer in Chicago during the first half of the 20th century. And Gingrich uses the name when he wants to attack President Obama. So who was Alinsky and what is his role in American politics? Lynn Sweet is Washington bureau chief for the Chicago Sun-Times. Sandy Horwitt is author of "Let Them Call Me Rebel: The Life & Legacy of Saul Alinsky."