Peter Brett Cullen is an American actor. He is best known for his roles as Dan Fixx in Falcon Crest (1986–1988), Sam Cain in The Young Riders (1989–1990), Governor Ray Sullivan in The West Wing (2005–2006), Goodwin Stanhope in Lost (2005–2008), Mark Keeler in Make It or Break It (2009–2012), Nathan Ingram in Person of Interest, and Michael Stappord in Devious Maids (2013–2015).