With a red, you'd have to be really careful. Tannins and heat can be very unpleasant. Big or super-ripe fruit would overpower the dish. Higher than typical acidity in the wine will help it from being overpowered. Cioppino can also negate a lot of complexity. I'd look for a rustic traditional Italian.
That said, the best pairing I've had was an Arcadian Chardonnay. The acidity stood up to the tomatoes, and the complexity played very well with the fish.