Earlier quoted context omitted.
Fox is by far the most popular news channel in the US and pretty close to bigger than the rest combined.
I've heard this explained by a comparison. If you have a block with four burger joints and one taco joint, you'd expect the taco joint to be the most popular. Not saying this is correct, but I thought it was an interesting analogy.
But explicitly the parent is saying that the taco joint is more popular than all of the burger joints _combined_. Which is not what I would have guessed.