Quintus Tullius Cicero, On Electioneering 21-23
“There are three things that will guarantee votes in an election: favors, hope, and personal attachment. The trick is giving these incentives to the right people. People are led to believe that they have reasons for giving support at the polls for extremely small favors– and that significant number of people you have attracted will not fail to understand that if they do not do enough for you in this crisis, that they will never have anyone else’s trust. And even though this is true, they still require an appeal and must be allowed the opinion that they, who have to this point been obligated to us, may hold us similarly obligated to them.
The voters who are motivated by hope–a class of people which is much more diligent and serious–you must persuade them that your assistance is ready for them immediately and there should be no mistake in them noticing that you are paying attention to what service they perform for you.
The third class of people I have mentioned, those of sudden friends, you must make more loyal by expressing your gratitude by adapting your speeches to the very reasons they seem to be eager about your candidacy; by showing that you feel the same way about them; and by implying that this relationship may grow into intimacy and long-term friendship.”
sed quoniam tribus rebus homines maxime ad benevolentiam atque haec suifragandi studia ducuntur, beneficio, spe, adiunctione animi ac voluntate, animadvertendum est quem ad modum cuique horum generi sit inserviendum. minimis beneficiis homines adducuntur ut satis causae putent esse ad studium suifragationis, nedum ii quibus saluti fuisti, quos tu habes plurimos, non intellegant, si hoc tuo tempore tibi non satis fecerint, se probatos nemini umquam fore. quod cum ita sit, tamen rogandi sunt atque etiam in hanc opinionem adducendi ut qui adhuc nobis obligati fuerint iis vicissim nos obligari posse videamur.  qui autem spe tenentur, quod genus hominum multo etiam est diligentius atque officiosius, iis fac ut propositum ac paratum auxilium tuum esse videatur, denique ut spectatorem te officiorum esse intellegant diligentem, ut videre te plane atque animadvertere quantum a quoque proficiscatur appareat.  Tertium illud genus est studiorum voluntarium, quod agendis gratiis, accommodandis sermonibus ad eas rationes, propter quas quisque studiosus tui esse videbitur, significanda erga illos pari voluntate, adducenda amicitia in spem familiaritatis et consuetudinis confirmari oportebit.