There has never been a vaccine requirement for voting. It has never been voted on. It has never gone to committee. It has never been proposed.

If you nevertheless are certain that that was or is the goal of one of the US's two major political parties, then you've reached a perplexing conclusion based on, I can only guess, no evidence, evidence imagined, evidence misunderstood, or evidence contained in a source that should be tossed into the garbage can.