Jan. 27, 2016 — Now less than a week before the Iowa Caucuses, five new polls of the Democratic presidential contest, all conducted within the same time period, arrive at very different conclusions. Three of the surveys find Sen. Bernie Sanders (I-D/VT) leading former Secretary of State Hillary Clinton, while two arrive at the opposite result.
All five polls — from CNN, the Emerson College Polling Society, CBS/YouGov, Fox News, and the American Research Group (ARG) — studied the Iowa Democratic electorate from Jan. 15-24. The sampling universes ranged from 258 likely Democratic Caucus attenders to 490 projected participants.
The Emerson College Polling Society, which is a group of students from Emerson College in Massachusetts who have established such a record of accuracy that the American Association of Public Opinion Research has granted them membership, employs the smallest sample size at 258 self-identified Democratic voters, while CBS/YouGov’s 490-person polling universe was the largest.