Polling techniques may account for erratic predictions in Virginia

At first blush, polling in Virginia’s closely watched race for governor looks all over the map, from a 17-point lead for Democrat Ralph Northam to an 8-point advantage for Republican Ed Gillespie. But what might appear to be a breakdown in pollster reliability may have a much simpler explanation: Not all surveys are conducted the same way, with variations in how questions are asked accounting for the large range of possible results in Virginia.

Read more here.