In January, Massachusetts Senator Scott Brown and his Democratic challenger Elizabeth Warren agreed to “the People’s Pledge,” a voluntary enforcement scheme designed to banish Super PAC and special-interest advertising from their campaign. To the amazement of campaign-watchers everywhere, thus far, it has worked. Brooke talks to Boston University Mass Communications professor and Campaign Outsider blogger John Carroll about why and what, if anything, the success of the Pledge means for the rest of the country.