The number of people who use the tired old "they feel the system is rigged" argument are mostly wrong. The majority of them are simply so self-absorbed (and generally materialistic) they can't possibly grasp the idea of structures existing outside themselves.
Look at the approval rating for congress or the President then contrast that with the approval rating of the military (72%), the police (57%), or small business (70%).
Source.Most Americans have the capacity to "grasp the idea of structures existing outside themselves".