The obvious answer to "who's going to watch the World Cup this summer?" is soccer fans. MLS viewers. People who already know what a false nine is. And the data backs that up — if you watch MLS, you're more likely to say you're all in on the World Cup this summer.

But there's a more interesting finding sitting right underneath that one. The single strongest predictor of World Cup interest isn't whether someone watches soccer. It's how many sports they watch overall. The more leagues a person follows — NFL, NBA, golf, whatever — the more likely they are to be dialed in come June.

This is essentially Byron Sharp's thesis playing out on a soccer field. Fandom isn't really a tribal identity — it's closer to a general disposition. There are people who get into sports, and people who don't. The World Cup, it turns out, is mostly just the next thing the first group is going to watch.

So if the "already sold" viewer is just a sports fan in general, that raises an uncomfortable question for anyone doing World Cup marketing: who are you actually trying to reach?