ABC, CBS and NBC have devoted 504 minutes to campaign news on their evening newscasts through last Friday, according to an analysis by the Tyndall Report, which studies the content of these programs. The previous high of 462 minutes at this point came in 2007, another year when no incumbent was running. Tyndall made no such measurements prior to the 1992 campaign.
Republicans have accounted for two-thirds of the coverage, partly because of the two debates and partly due to Donald Trump. The GOP front-runner accounted for 29 percent of the campaign coverage himself, Tyndall said. The two GOP debates have attracted record-setting audiences for Fox News Channel and CNN.
The three programs have also spent virtually the same amount of time on the controversy involving Democrat Hillary Rodham Clinton's emails as it has on her campaign, the report said.
NBC's "Nightly News" has spent 215 minutes on the campaign, the "CBS Evening News" 161 minutes and ABC's "World News Tonight" 128 minutes, Tyndall said.
Measurement of the presidential campaign began at the start of the 2015 calendar year.