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Somewhat.

I'd imagine that some of it comes down to having promotions and being out there. I think that if you can get a decently sized podcast to highlight your game you can do pretty well pretty easily, or even a bunch of people like me who are very willing to recommend what we like and have a more modest following you might see a potential to get followings.

It takes maybe ten thousand sales of a game to hit break-even (assuming a somewhat expensive budget of $250,000 or so), after you account for the cut that DriveThruRPG takes. Compare that to "best seller" ranks on DriveThruRPG. They start as low as 250 from what I've heard, so that's not exactly a tremendously high yardstick.