Bring water to a boil in a large Dutch oven or soup pot. Add clams, and steam 5 to 7 minutes or until shells open. Strain cooking water from Dutch oven into a container, discarding any sediment. Shuck clams into a bowl, discarding shells and any whole clams that do not open. Coarsely chop clams, and set aside.
Cook bacon in a large Dutch oven over medium-high heat, reserving 2 tablespoons drippings in pan. Set bacon aside.
Sauté onions and garlic in hot drippings over medium-high heat about 5 minutes or until tender. Add potatoes and thyme, and cook 5 minutes, stirring often. Sprinkle flour over potato mixture; cook 3 minutes, stirring constantly. Add reserved clam water and clam juice, and bring to a boil. Reduce heat and cook, uncovered, over medium heat 8 minutes or until potatoes are tender.
Add parsley and next 3 ingredients. Stir in clams and reserved bacon; cook over medium heat just until thoroughly heated.
Pour 2004 or 2005 Marques de Casa Concha Chardonnay. This fruity and buttery wine stands up to rich chowder but doesn't overwhelm.