Anyone who caught Stephen Colbert’s live Election Night special on Showtime last November might not have had very high expectations for his ability to thrive as a late-night comedian under President Donald Trump.

Besides the unfortunate presence of Mark Halperin, the special was notable for the way it allowed viewers to see Colbert reckon—in real time—with the unexpectedly dark future for an America that would be led by a man he had spent the better part of two years dismissing as a clown. Going off-script near the end of the grueling hour, Colbert decried the “poisonous” nature of American politics.

“We drank too much of the poison,” he declared at the time. “You take a little bit of it so you can hate the other side. And it tastes kinda good and you like how it feels. And there’s a gentle high to the condemnation, and you know you’re right.”

As Donald Trump was named president-elect and then later sworn-in before “the largest audience to ever witness an inauguration, period,” Colbert had a choice to make. He could either put the poison aside and try to welcome the 46 percent of voters who chose Trump over Hillary Clinton or he could lean in and risk an overdose. As could have been expected by fans of The Colbert Report, he chose the latter. The biggest surprise was how much it paid off.

Just as The Tonight Show’s Jay Leno’s broad play to middle America kept him solidly ahead of his late-night rival David Letterman for decades, Jimmy Fallon’s apolitical stance helped him keep NBC ahead of CBS after Colbert took over The Late Show in 2015.

At the end of 2016, Colbert trailed Fallon by an average of about 750,000 viewers each night. A year later, Colbert has an equally big lead over Fallon. According to the most recent Nielsen numbers obtained by The Daily Beast, Colbert averaged 3.7 million total viewers in 2017 compared to 2.9 million for Fallon. Those numbers represent almost an exact reversal from where they were the year leading up to Trump’s election.

While Colbert saw a 29 percent increase in ratings year-over-year, Fallon’s dropped by 21 percent. Despite his own stellar, news-making year, Jimmy Kimmel remains in perpetual third place with the same 2.3 million he averaged in 2016.

As the youngest of the three network hosts at 11:30, Fallon has managed to keep his lead with the coveted 18-49 demo, but Colbert has significantly closed the gap and could pull ahead there as well moving into 2018—another election year in which viewers will likely become even more engaged in the political realm. Assuming Special Counsel Robert Mueller’s investigation continues to escalate, that can only help Colbert, too.

There are a number of factors that may have helped Colbert achieve this new level of dominance in the late-night sphere, but the biggest has to be his relentless and unflinching focus on all things Trump.

Whereas at the beginning of his Late Show run, Colbert made some futile attempts to fashion his monologue around a wide range of news stories in the mold of those who came before him, from Johnny Carson to Fallon, in 2017, those monologues were almost always about Trump and nothing else.

On any given night this year, if you wanted to get caught up on the latest Trump-related outrage—and there was no shortage—all you had to do was tune into the first 10 minutes of Colbert’s show. Sometimes, you were even rewarded with a surprise appearance from Jon Stewart.

Even Trump himself seems to be aware of how he has unintentionally helped Colbert, as he revealed in an interview with Time magazine back in May. “You see a no-talent guy like Colbert. There’s nothing funny about what he says. And what he says is filthy,” Trump told Time. “The guy was dying. By the way they were going to take him off television, then he started attacking me and he started doing better.”

Those remarks came on the heels of a #FireColbert campaign by the alt-right on Twitter after the host said of Trump, “the only thing your mouth is good for is being Vladimir Putin’s cock holster.” Instead of buckling under the pressure and apologizing, Colbert doubled down, saying on his show, “I believe [Trump] can take care of himself. I have jokes, he has the launch codes, so…it’s a fair fight.”

And he could not have been more excited when Trump denounced him by name. In a moment that recalled how The Colbert Report’s “Stephen Colbert” would gleefully inject himself into the culture, the real Colbert blew a kiss to the president and said, “Don’t you know I’ve been trying for a year to get you to say my name, and you were very restrained—admirably restrained—but now you did it,” before pointing to himself and whispering, “I won.”

If there was any downside to Colbert’s laser-focus on Trump it was that it sometimes seemed to make it harder for him to react as strongly as was required to the few non-Trump stories that broke through the national conversation this year. He was relatively slow to take on the Harvey Weinstein bombshells and once he did, couldn’t help but make his jokes on the subject about Trump’s response.

Meanwhile, over on NBC, Fallon was still struggling to recover from the hair tousle that may have encouraged some to lean Trump last November. With Colbert delivering smart and pointed satire about the president on a nightly basis, Fallon’s softball Trump impression just wasn’t going to cut it anymore.

For his part, Colbert has publicly disputed the idea that Fallon’s friendly Trump coverage helped doom his show’s ratings. “The theory that that hair tousle made a difference is based on the supposition that Jimmy’s fans went to him for political acumen,” Colbert told the Times in April. “I don’t think so. They go there for fun. They go there for his nature, his spirit.”

He may have a point. But in a year Colbert rightly recognized on Election Night would be a challenging one for the country, “fun” is apparently no longer what most people are looking for in a late-night host.

The appetite for Colbert’s “political acumen,” on the other hand, is far from sated.