I like the story about how Francisco Ferrer got the funding for his school. He taught Spanish to this old, heavily religious and conservative, rich woman. He was able to change her mind by being respectful and not attacking her beliefs, but by having respectful discussion with her. He was never the one to initiate the discussions, which helped keep her from getting defensive and shutting down. And she ended up funding his rationalist secular school.

No one is a lost cause.