I will set up an election with candidates A, B and C, voter V, and claim maker K. A and B are the major party candidates, and C is a third party candidate.
Let's say voter V votes for candidate C. The claim is made by K that a vote for C is a vote for A. V casts a vote for C, so C gets one vote. But A also gets a vote? How did that happen? A vote must magically appear out of nowhere for this to be true. One vote is cast, but two are received! K needs to convince V of the mathematical equation 1 = 2. But this equation is false, and so is the claim that a vote for C is a vote for A.
Similarly, let's say V does not vote for any candidate. The claim is made by K that not voting is a vote for A. No vote is cast but A gets a vote that, again, magically appears out of nowhere? The equation that must be true is 0 = 1. But this, too, is false, and so is the claim that not voting is a vote for A.
As a result of the above, I would propose the following axiom: Candidates only receive votes that are actually cast for them.
Now, for a slightly different claim, I will add a piece of information that says that both candidates A and B are very undesirable candidates, and that B is "the lesser of two evils" in the eyes of K. K makes the claim that not voting for B is a vote for A. The error that K makes here is that K has already attributed V's vote to B according to K's own election plan. K is then guilt-tripping V (because K is attempting to be the lord of V's conscience) for failing to vote according to K's plan. Because a vote is already attributed to B, K believes he can take liberty to subtract a vote from B and claim that it goes to A. This is similar to the bookkeeping practice of subtracting from one column and adding it to another on a ledger. The money was already in the first column and was transferred to another column. But if no money was in the first column to begin with, it cannot be transferred to the second column. This claim is especially pernicious as K need to convince V that both equations of 0 = -1 and 0 = 1 are true. But they are both false, and the claim that not voting for B is a vote for A is doubly false.
One last scenario, the one in which we find ourselves today. We have two candidates, A and B, that are each perceived as being very evil, but with differing opinions as to which is the greater evil. Voters are taking such a stand against the candidate they perceive to be the greater evil that they create a motto such as #NeverA or #NeverB. They will voluntarily vote for a known evil just to prevent another evil from being elected. What is missed in all this is that #NeverA and #NeverB combined is a guarantee that an evil candidate is elected. No such guarantee exists for voter V that does not vote for either A or B, or who votes for a third party candidate. So, #NeverA and #NeverB are greater promoters of evil than the one who refuses to vote for a known evil. It is my hope that people can recognize the common fallacies presented to them each election season and reject them.