OC'ing at the voting area will be perfect. The line will be long enough that security is bound to get wind of you being there. And then, when they demand (on your recorder!) that a legal VOTER leave the polls, I think there will be a LOT more to the story.
Can private property owners enforce "no guns" rules if they choose to open up their property for voting? Legally, it seems the same as enforcing a dress code.