A jump in political advertising before the 2018 midterm elections buoyed third-quarter sales at Comcast despite a decline in cable-television subscribers.

Revenue at the cable communications division that includes video, voice, Internet, and advertising, rose 3.4 percent to $13.8 billion, even with the loss of 106,000 cable subscribers in the quarter, Comcast said in a statement. It was the sixth straight quarter that the video unit lost customers.