Fox News: Fox News Channel made ratings history Thursday night with the widely watched Republican presidential primary debate in Cleveland. More than 24 million viewers tuned in to watch the two-hour prime-time event, which featured the top 10 GOP candidates in the running for the 2016 presidential nomination. That makes it the highest-rated primary debate in television history as well as the highest-rated non-sports cable telecast of all time in total viewers. An average viewership of 24 million for one telecast is more than the combined viewers that watched the top 20 cable networks last week.