I wouldn't bother. In fact, unless you are going to run it long enough to really warm up, it could be detrimental.
Running it once a month is of no benefit over not running it at all. An argument might be made for running it every day or two for 20-30 minutes (sort of like normal use), but that's is a bit much to do, eh?
So leave it alone and relax. It will be fine as long as you take care of the batteries and use the fuel stabilizer additive.
Former owner of 2004 American Tradition and several other RVs
Home is in the Ocala Nat'l Forest near Ocala, FL