Pumpkin Soup with Sage and Ham

1 onion , chopped

1 carrot , chopped

1 rib celery, chopped

1/2 tart apple , such as Granny Smith, peeled, cored, and cut into 1/2-inch dice

2 cups canned pumpkin puree (from one 29-ounce can)

1/3 cup dry white wine

1 tablespoon dried sage

1 bay leaf

3 1/2 cups water

2 1/2 cups canned low-sodium chicken broth or homemade stock

1 1/2 teaspoons salt

1/4 teaspoon fresh-ground black pepper

1 1/2-pound piece of ham , cut into 1/4-inch dice