How to Tell Early if the Polls are Wrong

Sam Wang admits that everyone’s election forecasts “are, to an extent, built on sand. Historically, in any given year midterm polls have been off in the same direction by a median of 2 or 3 percentage points. Depending on the year, either Democrats or Republicans end up outperforming polls. In current poll medians, six races are within less than 2 percentage points: Alaska, Colorado, Georgia, Iowa, Kansas, and North Carolina. Therefore all six of these races could be won by Republicans…or all six could be won by Democrats.”

“The polls will be off, on average, by some amount in one direction or the other. Let’s call that average amount Delta. On Election Night, I will be watching returns carefully for clues about how large Delta is. In particular, I’ll be watching Kentucky and New Hampshire. Even though both races have a clear favorite, they have the advantage that voting ends fairly early in the evening. If either party outperforms polls in these states, that might indicate a broader trend nationwide.”