More Americans get their news from TV than from all other sources combined.

By far the most popular news programs are the ABC, CBS, and NBC evening news broadcasts.

Actually, those three are versions of the same broadcast, often on at the same time. Together their audience exceeds twenty million.

Despite the overall shrinking of television ratings, the combined evening news audience has remained stable. It is even growing. The evening news draws a larger audience than any entertainment show, be it Empire, Dancing with the Stars, or The Big Bang Theory.

The largest cable news program, The O’Reilly Factor, airs in prime time. Its audience tops out at three million.

The best most enduring entertainment programs often run no longer than five years. News programs give the network a consistent brand year in and year out. Competition among the three networks is particularly intense during a presidential campaign when news interest peaks. Through the years broadcasts have moved from second place to first based on the strength of their election coverage.

Enormous revenues are at stake. Sending reporters into the field costs—and makes—a lot of money.

We have chosen to follow the evening news broadcasts because of their enormous combined audience. These three programs compete on a level playing field. Each broadcasts for a half hour in the early evening. Each promises unbiased reports of the day’s most important stories. Each assigns its best correspondents to presidential campaign coverage.

Because the 6:30 p.m. audience skews older, and older viewers are mor likely to vote. They are more likely to be independents and undecided voters than those of the cable news broadcasts committed to a clear point of view.

We hope that a study of the coverage in these competing broadcasts will be a study of what constitutes best journalistic practice.