는 분 많다

lots of people who do that

분 is the respectful word for a person, so -는 분 is 'people who do that', spoken politely about others, and 많다 says there are a lot of them. Broadcasters use it constantly about their audience: plenty of people think that, it turns out a lot of people don't know this. Most lines add the honorific -시- as well, which is why you see 하시는 분 rather than 하는 분.

Register: polite, audience-facing