Not that simple.
This allegation, if true, could be raised by the McCain campaign's PR people and the press would have to report on it.
All depends on if its true.
The press will do everything they can to keep this story from being reported. They will accuse McCain of lying even if their is a video of the camapign ordering this action. They have lost all interest in objectivity. It makes one wish they were behaving like they did in 2004.