Thanks to Timo for pointing to a very interesting article about how groups and individuals influence minds and make converts.
It is written by a hypnotist who is giving away the secrets of powerful speakers.
"Over the years, I've conducted professional seminars to teach people to be hypnotists, trainers, and counsellors. I've had many of those who conduct trainings and rallies come to me and say, "I'm here because I know that what I'm doing works, but I don't know why." After showing them how and why, many have gotten out of the business or have decided to approach it differently or in a much more loving and supportive manner.
Many of these trainers have become personal friends, and it scares us all to have experienced the power of one person with a microphone and a room full of people. Add a little charisma and you can count on a high percentage of conversions. The sad truth is that a high percentage of people want to give-away their power--they are true "believers"!"