Preheat oven to 425F. Spray a 9 x 13 glass baking pan with cooking spray. In a bow mix together the tomato sauce/puree with the diced tomatoes. Add the oregano, garlic and onion powder and mix. Ladle enough sauce to lightly cover the bottom of the baking dish, approximately 1/2 cup. Lay the half the fish fillets down on top of the sauce. If you need to overlap them to get them to fit in the pan, it's fine. Sprinkle fish with 1/8 cup raisins and 1/4 cup olives. Add half of the remaining sauce to cover the fish. Add the remaining fish fillets and then add the remaining olives and raisins. Top with remaining sauce. Cover pan with foil and bake in the preheated oven for 30 minutes until the sauce is bubbling and fish is cooked through.