Pat the chicken dry with paper towels. Use kitchen shears to remove any excess fat or skin and place on a wire rack inside a baking sheet. Place the chicken uncovered in the refrigerator for at least 2 hours, or overnight.
In a small bowl, combine the granulated onion and garlic, salt, chili powder, and black pepper.
Use your fingers to carefully loosen the skin from the flesh of the chicken, careful not to completely remove. Sprinkle a teaspoon of rub under the skin and massage to distribute.
Apply rub to the outside of the chicken on all sides, reserving a small amount. Brush the skins with olive oil, then sprinkle lightly with more rub.
Preheat the smoker to 225 degrees. Add wood chips to the hopper.
Place the chicken in the smoker directly on the racks. Close the door and cook for 1 1/2- 2 hours, until the internal temperature of the chicken registers 165 degrees.
To get crispy skin, place the chicken skin side down on a hot grill for 4 to 5 minutes before serving.