Cook potatoes in boiling salted water to cover until tender, about 15 minutes. Drain and mash.
Combine potatoes, cream cheese and next 4 ingredients in a large mixing bowl; beat at medium speed with electric mixer until smooth. Spoon mixture into a greased 11" x 7" x 1-1/2" baking dish. Brush top of potatoes with melted butter and sprinkle with paprika. Cover and chill up to 24 hours.
Remove from refrigerator; let stand, covered, for 30 minutes. Uncover and bake at 350 degrees F for 30 minutes, or until heated.