It is possible to give a rabbit a bath, but it is not recommended. Bathing is stressful for a rabbit and can cause injury and hypothermia. Spot cleaning a rabbit is preferable.
If cleaning a rabbit is necessary, wet the area with warm water, and gently massage cat shampoo into the fur. Rinse thoroughly, and dry the rabbit as well as possible with a towel. Use a hair dryer on the lowest setting to complete the drying process and prevent hypothermia. Because a rabbit's skin is sensitive to heat, place a hand on the rabbit's skin in the path of the blown air to ensure that the temperature is comfortable.