There will be lawsuits for sure.
There was a good discussion on Fox last night about potential litigation RE PA. As it was discussed, the Constitution gives the State's Legislature the power to define election rules for their state. But what has happened in PA, and maybe elsewhere, was that election commission officials or others in the state government, made changes to the rules that were not approved by the State Legislature. Things like counting ballots that arrive after election day, not needing to match signatures on mailed in ballots, etc. Now there were law suits brought to stop that but the State Supreme court sided with PA and when it was kicked up to the US Supreme Court, it was a 4-4 tie on whether or not to hear the case, so it was kicked back the State Court and that ruling was upheld. The commentators view was that the Chief Justice, and all the others, really do not want to get involved in election issues, citing the fiasco of 2000. But I think they are going to now have to make some tough decisions. There are nine justices now so there will be no tie. If they had heard the case back in October before the election, things would have been decided one way or another, but they would not be 'picking the next president' as will probably be the case now that after the election there will be litigation no matter who 'wins' PA.