Although the four women featured in Rachel Lears’ documentary Knock Down the House are all Democrats, it’s not really a Democrat-vs-Republican movie. It assumes you share the liberal viewpoints of its subjects and then moves not to a battle on the political spectrum, but a larger fight of insurgents versus the establishment. Lears’ taps into the zeitgeist by showing people who feel that the system no longer works for them, and that it’s run by lobbyists and special interests that shut out the working class. Although Alexandria Ocasio-Cortez is the “star” of Knock Down the …