A History of Polling - 1948 - Dewey Defeats Truman
Perhaps the best known polling blunder in American history is the consensus prediction that Republican Thomas Dewey would defeat Democrat Harry Truman in the 1948 election. It didn't happen, leading to one of the most famous photos in election history - and the hope for all underdog candidates. The only election that compares with this one is our most recent one, the 2016 victory of Donald Trump over Hillary Clinton. So what happened? In my last article I wrote of how Gallup's polling had proven itself to be rather robust. However, it was not - nor is it- foolproof. I encountered a 1948 article in Time Magazine that spoke of him Gallup in the same glowing terms one might read about Nate Silver after the 2012 Presidential Election. However, that same article also referenced how poorly President Truman was doing in Gallup’s opinion polls (Time Magazine, 1948, pp. 21-23). In 1948, the Gallup Poll was one of three major polls which incorrectly predicted Dewey would def...
