If I wrote what I was thinking, it would be a felony. Maybe, at your point, the best option is to look carefully and make sure they’re both otherwise valid for this election. If one isn’t, then discard it. Other than that you can get with the DNC (i.e., the registrar of voters) and ask what to do...or just toss one in the garbage, after tearing it up.
What about liberals that lack such integrity?
Could they negate the votes of others?
/sarc off