Donald Trump counter-programmed Thursday’s GOP primary debate with his own prime time event. So whose show scored a bigger audience?

Answer: Fox’s debate. But it was the second lowest rated debate of the season. So Trump is certain to take credit for hurting the channel’s total viewership.

The first hour of Fox’s Trump-less debate had an 8.4 household rating, according to early Nielsen data on so-called metered markets.

This means 8.4% of American homes with TV sets were watching the face-off.

The second hour had an 8.3 rating, which means the audience was loyal even though Trump was absent.

By comparison, two of the cable channels that showed parts of Trump’s event, CNN and MSNBC, had about a quarter of Fox’s audience combined.

The most recent GOP debate, televised two weeks ago on the Fox Business Network, had a household rating of 7.4.

So Thursday’s debate was bigger — but not by much.

The other five GOP debates of the cycle have had household ratings ranging from 8.9 to 15.9.

Actual viewership numbers will be available later in the day on Friday. Fox News likely had 11 million to 13 million viewers for the debate.

One thing is ultimately unknowable: How many more viewers would have watched if Trump had been center stage?

Fox averaged a record-smashing 25 million viewers last August during the first debate of the season. Trump clashed with moderator Megyn Kelly that time — and avoided a rematch by skipping Thursday’s debate.

No one in the TV news expected Fox to surpass the 25 million mark this time. Still, the early household ratings might be seen as disappointing for Fox. There was incessant “will he or won’t he debate?” coverage for days leading up to the main event, which should have given Fox a boost.

Fox News will likely celebrate the fact that Thursday’s debate was higher-rated than the one two weeks ago. But its sister Fox Business Network was handicapped by weak distribution. (Its 7.4 household rating translated to 11 million total viewers.)

Perhaps a more fair comparison would be CNN’s December 15 debate, which had a 12.2 household rating and 18 million total viewers.

CNN and Fox News are on a relatively even playing field in terms of reach into cable homes.

Fox News also live-streamed Thursday’s debate; no streaming data has been released by the network.

Heading into Thursday night, Trump knew that his decision to forgo the debate was a test of his ratings magnetism.

Trump campaign manager Corey Lewandowski predicted that only “1 or 2 million people” would watch a Trump-free debate.

Maybe he was intentionally lowballing his estimate. When the final ratings come in, both Trump’s camp and Fox News will be spinning the numbers in their favor.

On the web, there were indications that Trump dominated political conversations even without being present at the debate.

Twitter said 36% of #GOPDebate candidate mentions were about Trump, way ahead of Ted Cruz’s 16% and Marco Rubio’s 13%.

On the other hand, according to Google, “debate live stream” beat out searches for “Trump live stream” by 170% on Thursday night.

Some television viewers were likely flipping back and forth with a remote control — or watching the debate on the big screen while keeping an eye on Trump via their smart phones.

It will be difficult to measure the total reach for Trump’s event since coverage was spread out across multiple TV channels, web streams and social networks.