As customers entered Mario’s Westside Market on a recent Friday afternoon, they might not have noticed the nondescript table and its occupants sitting outside. There were no signs or group logos, just papers impeccably stacked on a table beside a pile of pens. Nearby, a neatly dressed Antoinette Banks, 42, sat in a folding chair next to her friend, watching streams of people come and go from the neighborhood store on Martin Luther King Boulevard. “How are you doing?” Banks asked those nearing the door, catching their attention. “Are you registered to vote?”