In a large pot, cook the onion in the oil over medium heat until softened, about 8 minutes. Add the turkey and cook, stirring often to break up the lumps, until lightly browned.
Stir in the tomato sauce, grape juice, chili powder, oregano, cumin, salt, and pepper. Bring to a simmer. Cook 20 minutes or until thickened.
Serve with chopped red onion, cilantro, sour cream.
