The Statistical State of the Presidential Race

With fewer than 45 days left in the presidential campaign, it’s no longer a cliché to say that every week counts. And there are a few polling-related themes we’ll be watching especially closely this week.

This is probably about the last week, for instance, in which Mitt Romney can reasonably hope that President Obama’s numbers will deteriorate organically because of a convention bounce. …

But before we get lost in the weeds, let’s consider a more basic question. What did the polling look like at this stage in past elections, and how did it compare against the actual results? [cont.]

Nate Silver, FiveThirtyEight (NYT)