Rabble Rouser
October 8th, 2008
Answers.com: n. A leader or speaker who stirs up the passions of the masses; a demagogue.
Merriam-Webster: one that stirs up (as to hatred or violence) the masses of the people
Encylopedia.com:a person who speaks with the intention of inflaming the emotions of a crowd of people, typically for political reasons.