Why news outlets used entrance polls for Iowa caucus

We’ve come to expect the results of exit polls that predict the likely outcome of primary and general elections, but you may have noticed Tuesday night that news outlets used “entrance polls” instead. They’re done the same way, except that people are polled before they enter the caucus rather than after voting. CNN noted the distinction at the bottom of its chart showing the poll results. A key reason: time. Voting occurs all day, but caucuses don’t start until the evening. And caucusing can take longer than simply going into a booth and voting, with neighbors discussing the party platform and giving speeches to persuade one another to support their candidates. If polling were done after people left the caucus, the polls wouldn’t have much predictive value. || Related: “Momentum” was the dominant theme of news coverage in the two weeks leading up to the caucuses (PEJ)