Is personality a stronger attribute in argumentation than logic?

Some people believe that who ever looks more persuasive, or comes off as appearing to be more persuasive, would do better at actually being more persuasive than someone who only has sound logical reasoning in their arsenal. When ricahrd nixon was running against John F Kennedy for the presidency, they had a presidential debate that was watched on television and heard on the radio.The majority of people who watched the debate on television believed John F Kennedy won the debate. But those who listened to the debate on the radio believed that Mr Nixon won the debate. This lead some to ponder whether the visual aspect of the debate somehow seemed to give Mr Kennedy an advantage that had nothing to do with sound logical reasoning, and more to do with a more aesthetically appealing show of argumentation.

In the 90s there was a progressive metal band named tool (they happened to also be the first band I ever saw in concert). They had an interesting "song" that was just someone speaking in German in a dominating manner that was seeped in conviction, which was an obvious attempt to sound like adolf hitler. A lot of my friends who were fans of this band actually took the time to figure out what the speaker on the song (Maynard James Keenen) was saying. We were all kind of perplexed to find out that it was nothing more than a recipe for Mexican wedding cookies. We didn't understand why there was so much passion and frenzy put into the voice who was saying nothing of any importance to anybody except maybe those who may be planning a wedding. Then one day it hit me what the message of the song was. It doesn't matter what you say, it only matters how you say it. The words of the speaker of the song were of no importance, he was basically saying nothing. How he said it made it seem so important that people were going out of their way to find out what he was saying.  Perhaps that is how hitler could convince an entire nation of intellectual might to follow a disastrous policy of governance. 

This begs the question, is personality a more important tactic than logical reasoning?