I don't know the best way to finish this line. I want to hold a sign up at my polling place for all of the voting zombies. So vote or reply with the best ending (or change it up).
Of all the words you suggested, "compliance" actually means just what you intend to say, I think. The voter is complying with the two-party system by voting for one of the two parties.
I'm gonna go with ignorance. They want people to be stupid sheep. They repeat stupid crap over and over like "change" and "country first" to keep stupid people in their party.
Anyone with a brain wouldn't vote for a democrat or republican in this day and age. And so the two party system doesn't want the people to have a brain.
I went with subservience. Some people may mistake 'compliance' for some sort of citizens' duty. They comply with unconstitutional stuff all the time out of a twisted sense of patriotism.