Its posts were originally written by three lawyers who attended Dartmouth College together, namely John H. Hinderaker, Scott W. Johnson, and Paul Mirengoff.

On the weekend of Memorial Day, 2002, Hinderaker invited Johnson to start publishing on the Power Line site he had recently created.

[19] Power Line gained widespread recognition during the 2004 Killian documents controversy relating to a CBS report on George W. Bush's service in the Texas Air National Guard, starting with a post entitled "The Sixty-First Minute";[20][21] Powerline is credited with helping break the story.

[22][23] Conservatives (including Power Line, National Review Online and Little Green Footballs) referred to the controversy as "Rathergate".

After noting that the alleged documents used a proportional font, Power Line helped advance the story, triggering coverage by mainstream media outlets.