Kathy Bates was originally attached to play the role of presidential candidate, but unable to due to scheduling conflicts, and so Ann Dowd was cast instead.
Brian Cox and Stephen Lang also appeared in Manhunter (1986) the first adaptation of author Thomas Harris' novel Red Dragon in which Cox played Dr. Hannibal Lecter (although it's spelt Lecktor in Manhunter) and Lang played Freddie Lounds
This is the second time Brian Cox has starred in a production with the word "Independent" in it. His first was the TV Mini Series (2013) comedy "Bob Servant Independent," where he played an ordinary citizen who decides to run in an upcoming election as an independent candidate. Much of the comedy came from his character's lack of a filter in speaking his mind.