Well of course liberals are shocked that this movie would become popular.
It’s a cliche that liberals said after elections of both Nixon and Reagan that “how did these guys get elected? I don’t know anyone who voted for Nixon/voted for Reagan”.
The liberals live in a bubble land, and this is their Achilles heel. They truly are clueless about how this movie is resonating with people. And are clueless about how anyone would go to a movie which digs into Obama’s life and background.
No, they aren't clueless -- look at Mark Halperin's and the New York Times's reactions to Clint Eastwood's political sketch at the Republican convention. They know.
They're just deeply cynical, manipulative, and contemptuously instrumental.