Marco Rubio has a theory on why "House of Cards" was canceled ... the real D.C. is just way more dramatic.
We got the Senator on Capitol Hill Monday and asked about Paul Manafort's indictment, and Rubio clearly thinks it has nothing to do with meddling or collusion in the 2016 Presidential election.
As for "House of Cards," he giggled before giving his theory on the show getting the ax.
Netflix pulled the plug on the show several months ago ... before the Kevin Spacey revelations came to light.