But there is a big difference between "voted against X because it was a minor add-on to a bill that was overwhelmingly bad" and "voted against X when it was the focus of a bill; because the candidate is against X". The post in question implies the later, when the former is the actual truth (in my example).

I'm not trying to say someone is voting "wrong", because voting is a matter of opinion. But one should be able to base their opinion on actual truth, not lies. At the end of the day, if their opinion is based on lies they have been told, then it's really no different than secretly switching out the labels on the candidates in the voting machine.