Remove and discard the giblets and necks from hens. Rinse hens with cold water; pat dry.
Starting at neck cavity, loosen skin from breast by inserting fingers, gently pushing between skin and meat. Combine salt and pepper; rub under loosened skin. Insert 2 thyme sprigs and 2 garlic halves under loosened skin of each hen. Lift wing tips up and over backs; tuck under hens.
Place the hens, breast sides up, in an 11 x 7-inch baking dish. Pour white wine over hens.
Bake at 350° for 55 minutes or until a thermometer registers 180°, basting occasionally with wine. Let stand for 5 minutes. Discard skin.