The conventional wisdom is that whichever side loses the confirmation fight gets a boost in the midterms, because anger at the outcome motivates its voters. That’s probably right. I’d be in favor of confirmation even if I knew to a certainty that it would cost Republicans a few seats in Congress.
But Mary Katharine Ham made a plausible point on CNN earlier today: The Democrats were already pretty energized to vote this year, and there might be “diminishing returns” to their getting angrier.
If Ham is on the right track, it is possible that the viciousness of this confirmation battle will end up being a net positive for Republican candidates even if Kavanaugh is confirmed. Even if Republican voters’ anger fades by Election Day, that is, the difference in motivation will still be smaller than it was at the start of the summer.