The Nielsen company says an estimated 23.5 million Americans watched Super Tuesday election returns on six networks at 10 p.m. EST Tuesday.
During that hour, the top three broadcast networks had election specials, while CNN, Fox News Channel and MSNBC continued with their extensive coverage of returns that left Hillary Clinton and Donald Trump closer to their party nominations for president.
Nielsen says NBC averaged 5.7 million viewers at that hour. CBS had 5 million, Fox News Channel had 4.6 million, CNN had 3.9 million, ABC had 2.3 million and MSNBC had just under 2 million.
Between 8 and 11 p.m. EST, Fox News had 4.9 million viewers, CNN had 4.1 million and MSNBC had 2 million.
The Associated Press contributed to this article.