and that the Republicans don't go off the rails as the Democrats did with Kavanaugh (whether you think it right or wrong, Democrats overplayed their hand and blew up any chance of retaining certain red state Senate seats)
Exit polling from the 2018 races indicates that plenty of people had made their minds up before Kavanaugh's nomination became controversial, those who were seriously invested in the vote generally were already leaning strongly towards the candidate that they ended up supporting, and in some races (such as Florida, the closest by far) the Republican actually did better among those who cared less about that vote. At any rate, it's absurd to argue that the partisanship could've been there for Donnelly or Heitkamp to survive minus one controversy.