Combine 3 tablespoons tomato sauce, potatoes, cubed onion, eggs, garlic, salt, and pepper in container of an electric blender. Process until well blended. Combine tomato mixture and meat in a large mixing bowl; mix well. Set aside.
Core cabbage, and set aside. Place heads in hot water to cover until leaves are easily separated. Remove leaves. Cook leaves in boiling salted water 5 to 8 minutes or until just tender; drain. Place about 1/4 cup meat mixture in center of each cabbage leaf; fold ends over, and tie with string. Shred remaining cabbage; place in bottom of a large Dutch oven. Place cabbage rolls on shredded cabbage.
Combine remaining ingredients; mix well. Pour over cabbage rolls. Cover; simmer 2 hours. Remove rolls; serve with sauce.