Whenever it talked about candidate #1, it played grim, upsetting music and the narrator spoke in a deep, grim, threatening voice.
Whenever it talked about candidate #2, it played light, happy music, and the narrator spoke in a bright, cheery voice. It switched back and forth a few times. Wait, it gets better.
When the ad was over (and I didn't believe mountain_child at first, but he has 4 witnesses and swore that he was not, in fact, shitting me), the evil music and the evil voice came back on and said:
"If you vote for [candidate #1], you...will...die."