Heat oven to 350°F. Grease 13x9-inch (3-quart) glass baking dish. In large bowl, beat cake mix, water, oil and eggs with electric mixer on low speed about 30 seconds or until blended. Beat on medium speed 2 minutes, scraping bowl occasionally. Pour batter into baking dish. Bake 25 to 35 minutes or until toothpick inserted in center comes out clean.