State laws broken can run through state supreme then to SCOTUS. That was path of Bush v. Gore, if you are looking for an example.
Law is nothing but courts picking the outcome they want, then finding a rule to get that outcome. If they can't find a rule, they make a new one (See Sullivan and the Flynn case - many many example of this sort of power exertion)
Civil law is money damages or order for some type of performance. Anybody can start a civil suit.
Criminal law is activity that meets all the elements of a criminal statute. Only the state may start a criminal suit. This is where abuse of prosecutorial discretion plays. Ignore offenses by the protected class. Punishment by process for enemies.
States that ran election other than by rules set out by that state legislature (PA and GA are two, I think MI and WI perhaps also) ran unconstitutional POTUS elector contest.
That's the legal argument in a nutshell.
SCOTUS can simply make a finding that SoS is deemed to be the legislature for this purpose. It's nutty, but SCOTUS might as well be on LSD for all the sense it makes. We are governed by unscrupulous and broken institutions.
Siberia
Same way that ObamaCare was deemed a tax bill. Magic wand.