Sauté first 3 ingredients in hot oil in a large stock pot until tender; stir in next 13 ingredients (wine through lemon juice). Bring to a boil; cover, reduce heat, and simmer 1 hour. Let cool; cover and chill at least 12 hours.
Pry off apron or tail flap from crabs. Lift off top shell, saving cream-colored "crab butter" from inside the top shell, and discard shell. Pull out and discard feathery gills adhering to the body meat. Discard stomach mass, and break crab into left and right sections. Twist legs and claws from body. Cut each body section crosswise into 2 pieces. Crack legs with a wooden mallet. Set body pieces, cracked claws, and "crab butter" aside.
Discard any raw clams that are open.
Warm chilled tomato mixture in a large saucepan over medium heat, stirring occasionally, until thoroughly heated.
Place crab, clams, shrimp, and fish in a large stock pot. Pour the warm tomato broth over seafood; bring to a boil. Reduce heat, simmer 10 to 12 minutes. Discard any clams that did not open during cooking. Serve with sourdough bread; garnish, if desired.
Note: Dungeness is typically sold pre-cooked.