I would say what we all know as "fruit punch". candy that's flavored as fruit punch never tastes like actual fruit punch, but the flavor is kind of a mix of things - one ingredient isn't more distinct than the other.
Swedish Fish taste like RED. As stupid as that sounds, it is an actual flavor, like something tasting like blue. But if I had to choose something that it closely resembles, I would say strawberry citrus.
I have always thought the original red tastes like a combination of strawberry and raspberry, a little more of raspberry because it's not as sweet as strawberry. There is a sort of deeper flavor to it like a raspberry has over a strawberry.
I would say maybe a cherry or strawberry combo? Like a lot of people say, its a distinct flavor that only Swedish Fish have! I think it makes them even yummier and more unique because theres no other candies like them :)