Somebody else pointed out the Dylan documentary "Don't Look Back", from which several scenes were derived including the one where Bob Roberts and his blonde co-singer practice their hymn "We're marching for self-interest" while Bob checks his stocks on his laptop. In 1967, Joan Baez sang "Pretty Polly".
Polly, pretty Polly, come and go along with me / Before we get married some pleasure to seek
He led her over mountains and valleys so deep / Polly misjudged him and she began to weep
Sayin' Willie, Oh Willie, I'm afraid of your ways / The way you've been ramblin' you'd lead me astray
He said, Polly, pretty Polly, your guess is about right / I dug on your grave the best part of last night
I don't know much about US politics, although I sometimes wonder why they apparently have only two political parties since at least 200 years. But "Bob Roberts" is not an American movie, although it portrays the rise of a pure-bred American Hitler. Those two parties exist virtually everywhere, at least in every Western "democracy", and although they take turns every few years and have other names, the underlying power structure is the same, as their politics are increasingly the same.
This is a movie for the grassroots, a socio-political comment and a satire. It's supposed to stimulate the little gray cells, look at our leaders and our TV screens and ask, are we getting what we signed up for? What is the truth, and do I want to know?