Why Identifying Likely Voters Is So Hard

NBC News: “Predicting which party will prevail in the midterms isn’t as simple as picking up the phone and asking people how they will vote. About half of eligible voters are expected to turn out on Nov. 3, which means that a significant number of the people we reach in our polls will not vote.”

“Each firm has its own method of determining who is likely to vote, but all likely voter polls rely on two ways to identify that population: letting the voters tell us what they will do, or predicting whether someone will vote based on who they are. Sometimes these two things line up to produce similar outcomes, but this year, they push in opposite directions.”

“Because firms have to decide how to mix these two factors, since neither works perfectly, the results of a likely voter poll are affected by the choices different survey firms make.”