Re: Confused Brit
Election rules in the US are set by individual States which is why off year electoral races for the seemingly irrelevant Secretary of State positions are in fact extremely important. The Diebold scandal, such as it was, was perpetuated in what are colloquially known as "Red States" -- Republican dominated states. These states tend to use more restrictive voting rules -- reduced hours, reduced eligibility and so on.
BTW -- Capturing these positions wasn't a coincidence, its part of a winning strategy. That's what the Bernibros never really understood; we are where we are today because of a successful, ongoing strategy that's spanned decades, its nothing to do with individuals and specific elections. One other successful strategy has been district gerrymandering; since 2010 the House has a locked in Republican majority even though demographics should make many races competitive.