Rick--
For several years I have used a hooded silnylon rainsuit as a vb suit for sleeping in subfreezing temps. Lightwt polypro longjohns go next to skin, then the rainsuit, then a stretch layer (pp/Lycra balaclava, power stretch ski suit or alternately polypro stretch bike jersey and winter polypro biker tights, then the insulated clothing ( Parka, insulated pants, finally a 2lb synthetic overbag. This scheme will dry out the damp clothing from the day's hike with body heat and dissipate the moisture through the bag. Do not try it with a down bag or with temps above freezing! Lightweight.
Walt