WASHINGTON — (CNN) Early overnight Nielsen ratings suggest that Thursday’s Republican debate was not just the most-watched primary debate in history — it may have been twice as big as the previous record-holder.
The debate on Fox News had a 16.0 household rating between 9 p.m. and 11 p.m., according to Nielsen.
Translation: 16% of United States homes with TV sets tuned in.
Fox News usually has 1% or 2% of the household audience.
For the sake of comparison, the highest-rated Republican primary debates in 2011 and 2012 were watched by approximately 5% of households.
The Democratic primary debates in 2008 were bigger, but none of those ever topped 10%.
Interest in Donald Trump’s candidacy almost certainly drove viewership on Thursday night.
There are two important asterisks here: The household ratings may change somewhat once Nielsen completes its counting.
And raw viewership totals are not available yet. Nielsen will release that data sometime Friday afternoon.
But the preliminary ratings, known as “metered market overnights,” indicate that upward of 10 million viewers tuned to Fox for the prime time debate.
The first Republican primary debate in 2011, also on Fox, was watched by 3.2 million people.
There was also a surge — though much smaller surge — in viewership for the undercard debate at 5 p.m.
The ratings are good news not only for Fox but for other media organizations that are sponsoring Republican debates.
The “Trump show,” as some have called it, seems likely to continue into the fall.
The next debates are set for September 16 (on CNN) and October 28 (on CNBC).
Fox had high expectations for Thursday’s kick-off to debate season.
Rival executives and campaign aides also predicted unusually high ratings for the event, thanks to curiosity about Trump and the controversy over the “top ten” candidate criteria.
But the overnight numbers seemed to surpass everyone’s expectations.
There was speculation on Friday morning that it may go down in the record books as the highest-rated Fox News telecast ever.
On Thursday night there was immediate indication of the audience’s interest: the debate dominated social chatter on Twitter and Facebook.
Fox made the debate available online to cable and satellite subscribers, but many users on Twitter said they had a tough time accessing it.
A Fox spokeswoman confirmed the problems and said “an unprecedented, overwhelming demand caused server issues in the debate live stream.”
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