The Monmouth Rebellion historically failed quite brilliantly, but after reading a book on it I find that there are several PODs that could take it in different directions. Which is why I come to you with a question.
In OTL during William of Orange's invasion much of Britain quickly quit James' side to join Orange's force. Now this resulted from the fact that after the Monmouth Rebellion James became increasingly tyrannical, but I wonder if such defection is possible iduring the Monmouth Rebellion. Since several of the OTL traitors during the Glorious Revolution betrayed James simply for the political reason of being on the good side of William and Mary since it looked like William and Mary would win, if Monmouth was able to score a major victory and take Bristol might there be major defections among James' forces?