No campaign on the moral values can teach the rapists what punishing them with a death sentence can. Yes, you are right that rapists have always failed to feel the pain a victim suffers, but they are not alone to fail in feeling this pain. Each of those who have not suffered this unfortunate crime fails to realize the trauma. Had this not been the case, people would not have needed to come out on candle marches and pleaded to punish the criminals with the death sentence. Death sentence is the one and only solution to deal with increasing number of rapes in the country.
It will certainly help the society but in my opinion the problem with rapists is that they don't understand how extremely painful it is for the victim. No matter how much a girl tries to stop the rape, she cries/begs to let her go, but they fail to see the pain.
The problem with rapists is their behavior. We all had witnessed in the past what happened in the Nirbhaya rape case and now, Asifa. Death penalty, political assertions, candle marches and public outrage do not change the criminal behavior of rapists, if they did, the Delhi outrage in the Nirbhaya case would have created some fear in the minds of rapists and such rape cases wouldn't happen again.
Rapists’ behavior towards women hasn’t changed and it will not change any time soon unless we start working on ground levels. Government should start such campaigns that teach them moral values and change the criminal mindset of rapists.