Charlie Cook doubts that a Donald Trump defeat, which he considers quite likely, would have a significantly adverse effect on other Republicans running this year. Writing in the National Journal, Cook states, “even if Clinton wins by a much larger margin than, say, Obama’s win over Romney four years ago, I don’t think the down-ballot implications would be that huge.”
Cook gives two reasons for this assessment. First, there aren’t that many competitive races for House seats. Second, voter doubts about Hillary Clinton and the desire to check her power as president will, in Cook’s view, likely rein in a down ballot effect. The Democrats may well win the Senate, but probably not because of Donald Trump.
There’s a third reason why a Trump defeat might not spill over. As Cook suggests, traditional Republican voters who don’t support Trump are likely to turn out in large numbers to try to make sure Hillary has to deal with a Republican Congress. They might also be joined by folks who usually don’t vote but are inspired to by Trump. This, at least, is the theory espoused by many Trump supporters.
Some Trump voters who show up only because the tycoon is running may also think, what the heck, as long as I’m here I might as well vote for the other Republicans on the ballot. After all, Trump is endorsing, albeit grudgingly in many cases, most of these candidates.
Thus, down ballot Republicans could, in theory, benefit from Trump’s presence even if Trump loses by a substantial margin. Those who usually vote for these candidates will likely do so again and some who usually stay home might join them.
This scenario assumes, I think, that Trump isn’t blown out by Clinton. Cook seems to assume a Clinton victory by no more than 10 points.
But at the rate Trump is going, I can imagine him losing by 15 points. I’m not predicting that he will, but it’s hardly out of the question, in my opinion.
This would mean, among other things, that the Trump-only people didn’t show up after all. It might also mean that voters reconciled themselves to Clinton to a greater than expected degree.
In this scenario, Republicans should expect a significant down ballot effect — probably not large enough effect to flip the House, but sufficient to give the Dems a bigger than expected margin in the Senate.