Senator Marco Rubio (R-FL) did not have a good time at CNN’s town hall event Wednesday night. And Stephen Colbert noticed.

“The real star of the show was Florida senator and man who just received his cash from the NRA Marco Rubio,” the Late Show host joked in his monologue on Thursday. “Now, the crowd wasn’t exactly with Marco Rubio last night. And you know what they say: If they’re not with you, you’re Marco Rubio.”

Rubio got an unintended ovation from the crowd of mostly high school students when he said in order to ban some military-style weapons “you would literally have to ban every semi-automatic rifle that’s sold in America.”

“That is a guy who cannot read the room,” Colbert said, laughing. “Look, we’d have to get rid of guns and that’s a slippery slope to fewer dead people. Oh you’d like that? Fair enough.”

As Colbert mentioned, media figures have been calling Rubio “brave” for even showing up to the town hall, but he isn’t buying it.

“Here’s the thing,” Colbert said. “Just showing up isn’t that impressive. He works for those people. If your boss calls you into their office, you can’t say, ‘Yes, I hit a customer, yes, I turned turned the break room into a sex dungeon and yes I’m currently very high. But I showed up even though I knew you’d be mad. I should get some credit for that.’”