Another method is to be up-front about the nature of the propaganda, letting your audience know what you are doing as you do it to them. This impacts an audience at a Conscious level where they must actively consider the pros and cons of the issues. The propaganda comes from controlling the givens on the issues being discussed, while the audience focuses on which side of the issues they believe in.
A filmic example of this technique can be seen in JFK. By choosing a controversial topic (the assassination of President Kennedy) and making an overly specific argument as to what parties were involved in the conspiracy to execute and cover-up the assassination, Oliver Stone was able to focus his audience’s attention on how “they” got away with it. The issue of who “they” were was suspiciously contentious as the resulting media bru-ha-ha over the film indicated. Who “they” were, however, is not the propaganda. The propaganda came in the form the story’s given which is that Lee Harvey Oswald had help. By the end of the story, audiences found themselves arguing over which of the parties in the story were or were not participants in the conspiracy, accepting the possibility that people other than Oswald may have been involved.
From the Dramatica Theory Book