It seems that this statement is very difficult to argue in any meaningful way. Milton in his preface to his epic classic states that his purpose is to "justify the ways of God to men." It would seem very strange therefore if he were to identify himself with the character of Satan more than any other character. Critics have focused on the way that Satan is presented as being far more attractive and charismatic a figure than God, and yet the careful reader will identify a massive number of inconsistencies in his personality. He does indeed use powerful rhetoric, and his arguments do, at face value if nothing else, appear to be compelling and attractive, as his thinking behind how he will view hell reveals:
The mind is its own place, and in itself,
Can make a Heaven of Hell, a Hell of Heaven.
However, viewing his character throughout the epic it is clear that Milton is not presenting Satan in any way as a role model to follow. The inconsistencies in his character and the impact of deluded pride and arrogance on what he says and does are obvious, and therefore it is very difficult to find any justification whatsoever for the statement in this question.