By almost any measure, Senator Bernie Sanders is the frontrunner for the 2020 Democratic presidential nomination. But when he sat down with Trevor Noah on The Daily Show Thursday night, the host had one big question about his place in the field.

“This is an interesting time where this field is more diverse than ever before, but some people have said, all right, you have a diverse field, but it feels like the frontrunners are still old white men,” Noah said, citing Sanders and former Vice President Joe Biden, who has not yet announced his candidacy.

“You’re not talking about me, are you?” Sanders joked.

Pressing forward, Noah asked how Sanders responded to those who ask, “Isn’t it time for you guys to step aside?”

“Look, I think the American people have to make that decision, nobody else makes it,” Sanders, who will be 79 years old on Election Day 2020, replied. “But I think it is appropriate for people to say, OK, who has been talking about this issue when? Who had the courage to go forward and at what time? So it’s important not to look at just personalities. I think, in American politics, in general, we do too much of that.”

Then, the candidate deftly pivoted back to his core message of addressing income inequality: “What we need to do is focus on a progressive agenda and I’m proud of the fact that I have been a leader in fighting for that agenda for a long time.”

“You’re basically saying people have jumped on but you’re the O.G. of this idea,” Noah said in response, before acknowledging the way Sanders has been able to connect with young, progressive voters. But from there, he went on to question why Sanders has decided to hold a town hall event on Fox News later this month.

“Trust me, I know Fox News,” Sanders said. “I know who they are and I know the role that they are playing. So, to me, it is important to distinguish Fox News from the many millions of people who watch Fox News. And I think it is important to talk to those people and say, ‘You know what? I know many of you voted for Donald Trump, but he lied to you.’”

Later in the interview, Noah returned to the issue of Sanders’ age, asking what he does to keep himself healthy. “All I can say is thank god my health is good,” the candidate said. “As a kid, I was a long-distance runner. I had a lot of endurance, and I still do.”