This isn't just about the politicians (resigning)
Lost in all of the talk about Clinton, Franken, Moore, and Trump and if they should resign or should have resigned, is the voters who either did or might install them in office. Franken is a twice duly elected Senator. Clinton was a twice, duly elected President. Trump, pending the results of investigation into Russia's role is a duly elected President. Moore, if he God forbid wins, will be a duly elected Senator. In all of these cases, the voters knew what they were getting to some extent. They have a right, even if we think they are wrong, to have their wishes adhered to.
Trump, in my mind, should be impeached for violating the emolient clause of the Constitution and for colluding with Russia, but the harassment, voters made their judgement barring a criminal act that he gets convicted of, he shouldn't be removed for it.
Clinton shouldn't have resigned nor been impeached.
Franken, shouldn't resign and shouldn't be expelled unless it comes out he assaulted women as a Senator.
Moore, if he wins, shouldn't be expelled based on things he did before coming to the Senate.
Elections matter, the people speak, they have a right to be wrong. They didn't win their offices in a cracker jack box.