The most obvious and commonly accepted method is advertising. You promise you will do something, and I vote for you if the arguments that sustain that promise convince me.
But there are other ways, that rely on emotional manipulation.
A basic example is fear. You spread the idea that the opposing party wants to do something that many people fear, like restore communism. By repeating this idea over and over again, you can make people believe you without having to supply arguments or proof.
Another method is by exploiting vanity. For example, recently a party from an European country monopolized intelligence. They managed to induce through their media the idea that people who vote for the opposing party are stupid. So naturally people joined them, because they don't want to be identified as stupid. People who felt intelligent, but ignored by the "stupid" society fell for this easily.
Do you know any other methods that have been successfully used? How can voters realize when they are being manipulated?