The survey, published by The Des Moines Register for 76 years, is considered the gold standard for polling in the notoriously hard-to-predict state and is carefully watched as an early indicator of strength in the caucuses.

David Chalian, CNN’s political director, said on-air that CNN and The Register decided “out of an abundance of caution” not to release the poll after the network learned of a potential problem with the way the survey was conducted.