The Challenge of Reading the Midterm Polls

“With four months to go until this year’s midterm elections, perhaps the only thing clear about the fight for the Senate is that it will pose challenges to public polling,” Nate Cohn reports.

“There’s always the possibility that the polls could miss the outcome in a close contest. Polls have missed the result in three close Senate races in the last two cycles. But this year is particularly challenging. The rapid growth of partisan polls has contaminated the polling averages in states where surveying public opinion is already difficult. Many of these partisan polls employ dubious weighting and sampling practices. The combination will make it even harder for polls to nail the result.”