In a deep pot or Dutch oven, whisk together all ingredients except meatballs. Bring to a boil over medium-high heat.Add the meatballs and bring the mixture back to the boil. Reduce the heat to medium and continue to simmer for 35 minutes, stirring frequently. Cook until the sauce is thickened and meatballs are heated through.Serve with celery sticks and ranch dressing on the side.