Demagogue

A demagogue, or rabble-rouser, is a political leader in a democracy who gains popularity by arousing the common people against elites, especially through oratory that whips up the passions of crowds, appealing to emotion by scapegoating out-groups, exaggerating dangers to stoke fears, lying for emotional effect, or other rhetoric that tends to drown out reasoned deliberation and encourage fanatical popularity. Demagogues overturn established norms of political conduct, or promise or threaten to do so.