It is also notable that every other poll made at or around this time predicted Roosevelt would defeat Landon, albeit not to the extent that he ultimately did: most of these polls also expected Roosevelt to receive a maximum of 360 electoral votes. Subsequent research concluded that as expected, this sampling bias was a factor, but non-response bias was the primary source of the error - that is, people who disliked Roosevelt had strong feelings and were more willing to take the time to mail back a response. George Gallup's American Institute of Public Opinion achieved national recognition by correctly predicting the result of the 1936 election. Gallup also correctly predicted the (quite different) results of the Literary Digest poll to within 1.1%, using a much smaller sample size of just 50,000, while Gallup's final poll before the election predicted Roosevelt would receive 56% of the popular vote and 481 electoral votes: the official tally saw Roosevelt receive 60.8% and 523. This debacle led to a considerable refinement of public opinion polling techniques, and later came to be regarded as ushering in the era of modern scientific public opinion research. See also History of opinion polls References External links Landon in a Landslide: The Poll That Changed Polling The Literary Digest archive at HathiTrust 1890 establishments in New York (state) 1938 disestablishments in New York (state) Defunct literary magazines published in the United States Magazines established in 1890 Magazines disestablished in 1938 Magazines published in New York City Weekly magazines published in the United States