I expect reputable polls *just before the election* to be within 4%.
Right now I don’t have any of them to look at...
I agree with you that the polls get more accurate later in the election cycle. A new dynamic affecting public opinion polling for elections is the growing preponderance of early voting and absentee ballot voting. 37 states allow voting before election day.
The Commission on Presidential Debates has made their decision on which polls they will use to decide who makes the cut for this fall’s televised verbal sparring matches.
The pollsters that will determine who gets to be on stage come September and October are ABC News/Washington Post, CBS News/New York Times, CNN, Fox News and NBC News/Wall Street Journal.