Combine the sour orange juice, garlic, salt and pepper in a container suitable for marinating the chicken. Add the chicken pieces, cover and refrigerate 1 to 2 hours. Remove the chicken and blot it on paper towels. Reserve the marinade.
Warm the oil in a large Dutch oven over medium heat and brown the chicken pieces, in batches rather than overcrowding the pan. Return all the chicken to the pan. Add the onions and green pepper, sauteing with the chicken until the onions are translucent, about 3 minutes.
Add the reserved marinade, tomato sauce, wine, capers (if using; not in the ingredient list), olives, raisins, and potatoes. Reduce the heat to low, cover and simmer for 30 minutes. Transfer the chicken to a large serving dish and spoon the sauce over it.