LOS ANGELES - ABC and CBS said Monday they would offer gavel-to-gavel coverage of the Democratic and Republican conventions this year over the Internet as well as periods of prime-time coverage over their broadcast networks.
Both ABC News and CBS News will offer one hour of prime-time coverage on three nights of each convention.
Last week, NBC said it would offer one hour of prime-time coverage each night of both conventions, supplemented by five hours of coverage each night on cable channel MSNBC.
Political conventions have become staged "publicity making machines" for both parties and thus inappropriate for the television networks to cover to the extent they once did, "Nightline" host Ted Koppel told the Television Critics Association Monday.
Koppel walked out of the Republican convention in 1996 and did not attend the Democratic convention that year to "make a statement that conventions had significantly changed," he said.
But both he and "World News Tonight" anchor Peter Jennings said it was proper to use new technology to provide more extensive coverage.
"I really do think it is our responsibility to give the parties an opportunity to put their spokesmen in front of the American people," Jennings said.
Jennings will host the network's prime-time coverage, as well as 19 hours of coverage that will be made available to local stations to broadcast over their digital signal.
A special digital television tuner is required to pick up the signal, although many local stations have deals with cable companies to carry the channel on digital cable services.
Monday, ABC News President David Westin said the digital television broadcasts should be available to 80 percent of the country.
Live coverage will also be available over ABC's broadband Internet service, "ABC News Live."