Somewhat of a slow-burner, Rosemarie DeWitt (who is the granddaughter of boxer James Braddock, the subject of the film “Cinderella Man,” in which she had a cameo) spent a good decade or so building up a formidable reputation in the theater, but really only started to make an impact on screens five or so years ago. After a brief year on the hostage negotiation series “Standoff” (which was cancelled quickly, but had the benefit of introducing DeWitt to co-star Ron Livingston, who she later married), DeWitt impressed with a recurring role as Don Draper’s mistress on the first season of “Mad Men.” Within a year, she was the title role in Jonathan Demme‘s “Rachel Getting Married,” and while co-star Anne Hathaway won most of the acclaim for the film, DeWitt was again terrific, and along with that year’s “Afterschool,” it put the actress properly on the map. She’s gone from strength to strength in the last few years, with 2012 marking three very good turns from the actress in the shape of “Nobody Walks,” “Promised Land” and in particular “Your Sister’s Sister,” which won her a Spirit Award nomination yesterday. Mainstream cinema hasn’t quite caught on yet, with her most prominent studio role to date a somewhat thankless part as Ben Stiller‘s wife in flop comedy “The Watch.” But with a reunion with Lynn Shelton in next year’s “Touchy Feely“ on the way, hopefully her profile will continue to grow. She’s someone we can absolutely see ending up with an Oscar nomination in the next few years.