By Brian Stelter

WASHINGTON (CNN) — About 46 million Americans watched President Trump’s first State of the Union, according to Nielsen ratings data.

The viewership figures were down, but only slightly, from Trump’s joint address to Congress last winter.

Tuesday’s ratings were also slightly lower than the comparable State of the Union speech delivered by President Obama in 2010. (Obama drew 48 million that night.)

But it’s hard to say whether that’s a consequence of Trump’s relative unpopularity, or the increasingly fragmented state of television.

In any case, the State of the Union remains one of the most-watched events of the year — a unique opportunity for a president to outline his priorities.

The Nielsen ratings count up TV viewership of the speech across twelve broadcast networks and cable channels. The ratings do not include out-of-home viewership or live-streaming.

Across all twelve, the total was 45.8 million viewers during the speech.

Fox News had the biggest audience by far, with 11.7 million viewers during the speech, breaking a State of the Union record for the channel.

NBC and CBS averaged 7 million viewers each, ABC averaged 5.4 million, the Fox broadcast network had 3.6 million, CNN had 3.1 million, and MSNBC had 2.6 million. Some smaller channels rounded out the rest. Another 3.5 million viewers watched on Spanish-language networks.

Fox’s record audience reflects its status as the favored network of Trump supporters. Fox’s pro-Trump hosts routinely deride the rest of the national news media as “fake” and worse.

Presidents typically enjoy relatively high ratings early on, and lower ratings for subsequent State of the Union addresses.

Obama, for example, averaged 31 million viewers for his final State of the Union in 2016.

In Trump’s case, there was an expectation that his supporters were far more likely to tune in than his detractors.

The speech was relatively long, with notes of bipartisanship but many appeals to his base.

What we saw was Trump “with one hand reaching out his hand to Democrats, and with the other hand, holding up a fist. And this is almost the conundrum of Donald Trump,” Jake Tapper said on CNN afterward.

“I think this reality TV president was trying to create a new reality — a new political reality for himself,” CBS’s Norah O’Donnell said. “And he was trying to sort of take a giant eraser to all those really divisive tweets to try and find a new way to communicate with the American people. But it doesn’t erase what has been his record.”

It remains to be seen whether the speech will have staying power.

In the nearly 24 hours since the speech, Trump has not stepped on his message with any rogue tweets or announcements.

But other big stories have already overshadowed the speech: A deepening dispute between the FBI and Congress, a train crash in Virginia, and another GOP retirement.

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