DES MOINES, Iowa — The only poll that mattered before the only poll that matters has been canceled.
The Des Moines Register and CNN decided late Saturday not to release their highly anticipated poll of Monday's Iowa caucuses after a potential error was brought to their attention by the campaign of Pete Buttigieg, the former mayor of South Bend, Indiana.
"Nothing is more important to the Register and its polling partners than the integrity of the Iowa Poll," Carol Hunter, the Register's executive editor, said in a statement. "Therefore, the partners made the difficult decision to not to move forward with releasing the Iowa Poll."
The Iowa Poll, conducted by Ann Selzer for the Register and other media partners — in this case, CNN and Mediacom — is widely considered to be the most accurate survey of the state, and its results have often predicted the outcomes of elections that others missed.
But on Saturday, a Buttigieg supporter who said they were surveyed by a survey taker working for Selzer, claimed that Buttigieg's name was left off a list of candidates' names the survey taker read. The supporter raised the issue with the campaign, which took it up with Selzer.
After looking into the issue, Selzer and the media partners said they could not guarantee that the results had not been compromised and decided to kill the final poll before Monday's crucial first-in-the-nation caucuses.
Download the NBC News app for breaking news and politics
"The Register has published the Iowa Poll for 76 years, and it is considered the gold standard in political polling. Selzer & Co., which conducts the poll, is recognized for its excellence in polling. It is imperative whenever an Iowa Poll is released that there is confidence that the data accurately reflects Iowans' opinions," Hunter said.
Lis Smith, Buttigieg's senior communications adviser, said in a tweet that her campaign "applaud(s) CNN and the Des Moines Register for their integrity."