Director Rachel Lears began work on Knock Down the House shortly after the election of Donald J. Trump to the office of the President of the United States in 2016. Upset and disillusioned with a political system which would elect Trump, she sought to create a film would bring hope to the Democrats and Independents who didn't like Donald Trump about the future of politics in the United States.
To that end, she reached out to a groups like Brand New Congress and Justice Democrats to find Democrats who are "charismatic female candidates who [are]n't career politicians, but had become newly galvanized to represent their communities." That search led to four candidates (one of whom won her election against all odds): Alexandria Ocasio-Cortez from New York (who won her election), Amy Vilela from Nevada, Cori Bush from Missouri, and Paula Jean Swearengin from West Virginia.
First, though, Lears needed to fund her project. So, she headed to popular crowdfunding site Kickstarter, where she raised just $28,000. That was enough for Lears to finish the film in time for the Sundance Film Festival in January 2019, at which point and time Netflix acquired the rights to the film for a whopping $10 million dollars (one of the largest sums ever paid for a documentary).
Ultimately, the film received very good reviews from critics but less-than-stellar reviews from audiences, indicating that the film did its job (to inform the public about these candidates).