Attack of the robocalls

Barack Obama's campaign tonight offered a new defense to "robocalls" from John McCain and Republicans: a video, called "Robots Attack" that spoofs those old science fiction movies.

Using black-and-white scenes from old movies and scary music, the ad opens on screen with "This Halloween, America faces a new menace."

It shows a robot saying one of McCain's automated phone calls trying to link Obama to William Ayers, who led a group that bombed government buildings during the early 1970s but was a respected professor by the time Obama served on nonprofit boards with him two decades later.

"Defeat the robots! Contact voters now!" the on-screen message urges Obama backers.