Preheat oven to 350 degrees. Butter a 13-x9-inch baking pan.
Bake the sweet potatoes until a fork inserted in the center meets no resistance, about 45 minutes. Remove the skins and mash until smooth. In a large bowl combine the potatoes, orange juice, cinnamon, nutmeg, mace, and salt and beat until smooth. Spoon the mixture into the prepared pan and sprinkle with sugar, pineapple, and raisins. Arrange a single layer of marshmallows over the top and bake until the marshmallows are lightly browned, about 20 minutes. These can be made a day ahead, covered, and refrigerated, then baked about 35 minutes before serving.
Makes 8 to 10 servings