Sanders is talented and thrives on platforms that doesn’t actively try to sabotage him. Therefore I wasn’t surprised that he performed well with Rogan; many comments from those that are undecided on American politics seemed to think so too.
Then I found BoingBoing’s story about his appearance and noticed how different they saw it. BoingBoing is left-leaning, at least according to American politics, and fairly pro-Sanders. They, too, thought Sanders did well but was surprised that he chose to appear with Rogan and that commenters seemed to like it.
It seems to be because Rogan sometimes have had right-wing people on his show, and he might be right-leaning himself.
More and more people think that means that he will be unfair to those on the left and that his audience will be blind and deaf to anything that doesn’t align with that. The partisans see partisans everywhere.
But Rogan is a good interviewer and his platform isn’t his political views but how interesting his interviews are. So his audience is who is interested in that. Naturally Sanders would perform well there.