I can tell you that for a fact, answering polls can have a huge impact on the final result. You ought to SEE the thought process that goes into interpreting the polls and what actions it means a candidate should take. Scary stuff.
And again, I am not saying that I think only military types should vote. The fact that it would require some modicum of effort to earn the privelege, perhaps the same people would invest a little time into looking into the issues surrounding a candidate rather than making a snap decision based on nothing but a list of names.