In a soup pot melt the butter over medium heat. Add the onion, celery, carrot, and garlic. Sauté until soft.
Stir in the potatoes, broth, salt, pepper and Old Bay seasoning. Cover and simmer 20 minutes or until the potatoes are cooked through.
Reduce heat to low and add the crab, half-and-half, creamed corn and parsley, and simmer gently until hot.
Ladle the chowder into warm soup bowls and serve immediately.