Michael Moore's "Fahrenheit 11/9" failed to heat up the weekend box office.

The Oscar winner's latest documentary landed at a disappointing No. 8 over the weekend with an estimated $3.1 million, according to early studio estimates. That's about half of what it was expected to pull in according to pre-release tracking.

The film, which finds Moore taking on President Trump, the Flint water crisis and other hot button issues, launched in wide release in more than 1,700 theaters and brought in a mild $1,800 per screen.

Fourteen years ago, Moore's "Fahrenheit 9/11" set the box office on fire, pulling in $23.9 million its opening weekend on its way to a $119 million gross, the highest ever for a documentary. (By quite a lot, in fact: No. 2 on the list is "March of the Penguins," with a $77.4 million haul.)

It has been a stellar year for documentaries, with "Won't You Be My Neighbor," "RBG" and "Three Identical Strangers" all doing solid business at the box office.

But political docs have had a tougher time finding audiences; last month, Dinesh D'Souza's "Death of a Nation" opened at No. 13 with $2.4 million, and has grossed just $5.9 million to date, well below the grosses of his films "2016: Obama's America" ($33.4 million) and "Hillary's America: The Secret History of the Democratic Party" ($13 million).

Moore's film has done well with critics and audiences: On Rotten Tomatoes, the film has received a 79 percent approval rating, and audiences gave the film a CinemaScore rating of A.

"Fahrenheit 11/9" was one of three wide releases to disappoint at the weekend box office; "Life Itself" (No. 11, $2.1 million) and "Assassination Nation" (No. 15, $1 million) also performed below expectations.

"The House With a Clock in its Walls" opened strongly at No. 1 with $26.8 million, followed by "A Simple Favor" ($10.4 million) and "The Nun" ($10.2 million).

agraham@detroitnews.com

@grahamorama