WASHINGTON (BLOOMBERG) - Just over 50 million TV viewers tuned in to watch election returns on major US TV networks on Tuesday (Nov 3) night, a decline from four years ago that may have reflected voter exhaustion and the lack of a clear winner.

Fox News led overall, with an estimated 13.6 million viewers in prime time, according to early Nielsen data supplied by the network.

AT&T Inc.'s CNN finished second with 9.1 million. Among broadcast networks, Walt Disney Co.'s ABC was first with an audience of 6.1 million. The ratings are preliminary, and Nielsen will release a total later that includes a larger universe of networks.

The election-night audience had been trending up over the past 20 years with the growth of cable TV. The most recent high was 71.5 million viewers in 2008, when Barack Obama defeated John McCain to become the first African-American US president.

Four years ago, about 71 million viewers tuned in to watch the results on 13 networks offering live coverage during prime time, according to Nielsen. That was up from 66 million total viewers in 2012.

Fox News, a division of Fox Corp., made some early calls election night, including identifying Democrat Joe Biden as the winner in both Virginia and Arizona.

Audience trends have been mixed this election season. Viewers for the national conventions was soft, continuing a trend of declines for those events.

But Americans flocked to the two debates between Donald Trump and Biden. The first debate delivered 73.1 million total viewers, the third-best showing in the last four decades.

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