Departing anchor asks audience to support show or network will pull itNEW YORK - As he walked out the door, Ted Koppel couldn’t resist one last dig at the network that almost dumped him three years ago. Koppel, in his final broadcast Tuesday after more than 25 years as anchor of ABC News’ “Nightline,” asked his fans to give successors Martin Bashir, Cynthia McFadden and Terry Moran a fair break when they start on Monday. “If you don’t,” he said, “I promise you the network will just put another comedy show in this time slot. Then you’ll be sorry.”