those two ideas aren't mutually exclusive. rigging an election isn't a binary switch that turns a loss to a win. it's slightly more pressure on one side of the scale. you ballot harvest a few extra votes for your side. you have your poll workers fill out some ballots in the names of people that didn't show up to vote. you register people the same day and let them vote without any proof of residence. all these things can add up and tip a 50:50 election to a 49:51. what they can't do is turn a 55:45 into a win.
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