How polling methodology affects Ralph Northam’s lead in the Virginia governor’s race

Final polls show Democrat Ralph Northam holding a slight edge over Republican Ed Gillespie before Tuesday’s election for governor of Virginia. But a lot of uncertainty remains, especially given the typically low turnout in off-year elections and recent poll misfires in Virginia. Polls significantly underestimated Republican candidates in the 2013 gubernatorial election and 2014 contest for U.S. Senate.

Two recent surveys illustrate the challenge of determining who is actually likely to vote. Based on different methods of identifying likely voters, Northam’s lead could be as large as eight points and as small as two points. CONT.

Scott Clement & Mark Blumenthal, Monkey Cage