There's quite a lot of firepower already stacked up behind Ava DuVernay's Martin Luther King Jr. biopic "Selma." Brad Pitt and Plan B partners Dede Gardner and Jeremy Kleiner are producing (hot off a Best Picture Oscar win for "12 Years a Slave") along with Oprah Winfrey, and today, a new actor has been announced for the cast.

The Wrap reports that Oscar nominee Tom Wilkinson ("In the Bedroom," "Michael Clayton") is in early talks to play President Lyndon B. Johnson in the film, which will star David Oyelowo ("Lee Daniels' The Butler") as King in the story of the landmark 1965 voting rights campaign.

This is one of three MLK films that have been in the works, the others being "Memphis" (penned by Paul Greengrass with Scott Rudin producing) and an Oliver Stone/Jamie Foxx project set up at DreamWorks that has the backing of the King family. Those projects were very slowly coming together, but "Selma" is the one moving full steam ahead.

A former publicist, DuVernay is coming off of 2012's "Middle of Nowhere," which won awards at the Sundance Film Festival, the Gotham Awards and the Independent Spirit Awards. Lee Daniels had formerly been on board for "Selma" (and brought Oyelowo to the project), but DuVernay's rewrite of Paul Webb's original screenplay convinced Winfrey to join the project, according to The Wrap.