Written more than a century ago:
Electors [or voters as we commonly refer to them today] are persuaded in particular for the flattery of their vanity and their greed. They must be overwhelmed with the most extravagant blandishments, and there must be no hesitation in making them the most fantastic promises. If the electors are working class, it is impossible to go too far in insulting and stigmatising employers of labour. As for the rival candidates, an effort must be made to destroy their chance by establishing by dint of affirmation, repetition, and contagion that they are arrant scoundrels, and that it is a matter of common knowledge that they have been guilty of several crimes. It is, of course, useless to trouble about any semblance of proof. Should the opposition be ill-acquainted with the psychology of crowds, they will try to justify themselves by arguments instead of confining themselves to replying to one set of affirmations by another; and they will have no chance whatever of being successful. ~ Gustave Le Bon, Psychology of Crowds, 1895
Seems the more things change, the more they stay the same because whether a crowd is together physically or connected electronically by television, radio or the internet (via social media), it adopts "a slight aptitude for reasoning, the absence of a critical spirit, irritability, credulity, and simplicity." (Le Bon)
This is one reason why the founding fathers abhorred the concept of universal suffrage (one person, one vote). Crowds (parties, associations) exhibit the lowest common level of intelligence when selecting and electing their candidates.
They are enamored by a candidate's prestige according to Le Bon:
Of capital importance ... is the necessity for the candidate of possessing prestige, of being able, that is, to force himself upon the electorate without discussion. The reason why the electors, of whom a majority are working men or peasants, so rarely choose a man from their own ranks to represent them is that such a person enjoys no prestige among them. When, by chance, they do elect a man who is their equal, it is as a rule for subsidiary reasons — for instance, to spite an eminent man, or an influential employer of labour on whom the elector is in daily dependence, and whose master he has the illusion he becomes in this way for a moment The possession of prestige does not suffice, however, to assure the success of a candidate.
(But) an orator who knows how to make use of ... means of persuasion can do what he will with a crowd.
And while not all crowd psychology is necessarily used for ill-gain, it's important we remember, primarily during our contentious national elections, that some of the greatest political despots of the 20th century studied Le Bon's work.