A sequel to “Game Change,” the TV movie about the 2008 presidential race and Sarah Palin, is in the works, according to HBO.

Political reporters Mark Halperin and John Heilemann, who wrote the best-selling book that the movie was based on, are writing a new book, “Double Down: Game Change 2012, ” about the 2012 presidential campaigns of Mitt Romney and Barack Obama.

HBO has optioned the book, due out in the fall, to make a new movie, the premium cable network said yesterday.

The movie would not be ready until 2014 at the earliest and, as yet, there is no word on which camp — Romney’s or Obama’s — the film will focus on.

The first film, which starred Julianne Moore as Sarah Palin and Ed Harris as John McCain, was the most awarded TV movie of last year.