Chocolate Chip Rum Cake

1 (18.25 ounce) box Duncan Hines yellow cake mix
1 large box instant chocolate pudding
4 eggs
1 cup sour cream
1/2 cup vegetable oil
12 ounces semisweet chocolate chips
1 teaspoon vanilla extract
6 to 8 tablespoons rum

Grease and flour a Bundt pan. Mix all ingredients for 12 minutes at high speed of electric mixer. Bake in Bundt pan at 350 degrees F for about 1 hour. Cool; invert onto cake platter.