Des Moines Register Poll of Iowa Caucusgoers Abruptly Shelved

DES MOINES — A highly anticipated poll of Iowa Democrats, set to be released two days before the presidential caucuses, was shelved on Saturday night after complaints about irregularities in the methodology.

The concerns, raised by aides to former Mayor Pete Buttigieg, prompted CNN to cancel an hourlong special organized to release the results of their survey, conducted with the Des Moines Register.

The Buttigieg campaign said that an Iowa supporter received a poll phone call from an operator working for Ann Selzer, who runs the Register’s famed Iowa Poll, but that the name of the former mayor of South Bend, Ind., was not listed on the menu of options, according to a senior official on Mr. Buttigieg’s campaign.

The survey 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.

“It was brought to CNN’s attention earlier this evening that somebody who was questioned for the survey raised an issue with how their interview was conducted,” Mr. Chalian said. “We weren’t able to determine exactly what happened during this person’s interview and we don’t know whether it was an isolated incident.”

This supporter then relayed what had happened to Mr. Buttigieg’s campaign, which contacted Ms. Selzer about it. But the Buttigieg aide, who requested anonymity to discuss a private conversation, said the pollster offered little information about how many surveys the former mayor and one-time Iowa front-runner was left off.

Iowans typically finalize their choice late in the campaign, often deciding in the days before the caucuses occur. The late-breaking nature of the state’s political culture lends the poll outsized influence, with the power to fuel a last minute surge in the state or can be an early dirge for candidates struggling.

Recent surveys have shown a fluid race, with Senator Bernie Sanders gaining momentum as other leading candidates trail close behind.