Preheat oven to 350°. Combine first 6 ingredients. Add beef and pork; mix lightly but thoroughly. Shape into 1-1/2-in. balls. Place on a greased rack in a 15x10x1-in. pan. Bake until a thermometer reads 160° (165° if using ground turkey), 35-40 minutes.
Meanwhile, in a large saucepan, combine sauce ingredients; bring to a boil, stirring frequently. Reduce heat; simmer, uncovered, 10 minutes. Gently stir in meatballs.