THIS campaign is ending just in time before someone gets hurt. John Kerry's stepson, Chris Heinz, 31, displayed his mother Teresa's famous lack of rhetorical restraint at a recent campaign event with a group of Wharton students. Philadelphia magazine reports: "Heinz accused Kerry's opponents - 'our enemies' - of making the race dirty. 'We didn't start out with negative ads calling George Bush a cokehead,' he said, before adding, 'I'll do it now.' Asked later about it, Heinz said, 'I have no evidence. He never sold me anything.'" Heinz also reminded writer Sasha Issenberg of Pat Buchanan by saying, "One...