Just for the fun of it, I went to the Campbell's Soup website, and here you are:

Fast & Easy Tomato Soup Spice Cake
Prep Time: 10 Min.
Cook Time: 35 Min.

1 package (about 18 ounces) spice cake mix
1 can (10 3/4 ounces) Campbell's® Condensed Tomato Soup
1/2 cup water
2 eggs
Directions

1. Preheat oven to 350°F. Grease and lightly flour two 8- or 9-inch round cake pans.
2. In large bowl mix cake mix, soup, water and eggs according to package directions.
3. Pour into prepared pans. Bake 25 minutes or until toothpick inserted in center comes out clean.
4. Cool on wire racks 10 minutes. Remove from pans and cool completely on wire racks.
5. Fill and frost with your favorite cream cheese frosting. Serves 12.