Fifteen months before President Franklin Roosevelt's unprecedented election to a third term in 1940, the majority of Americans were not inclined to support him. Only in October 1939, after the start of World War II in Europe, did Americans' desire to keep Roosevelt in office begin to mount, and it wasn't until the spring of 1940 that support surpassed 50%.
In a June 1940 news article, George Gallup wrote, "Sentiment for a Roosevelt third term rose sharply when the Nazis began their world-shaking invasion of Holland, Belgium and France May 10 but has levelled off in recent weeks in the American Institute's continuous surveys of public opinion. As a result of the rise, the number of voters favoring a third term has reached a majority for the first time since the president has been in office."
More specifically, the percentage of Americans backing Roosevelt for a third term rose from 40% in August 1939 to 46% in October (after the outbreak of World War II), and then to 57% in May 1940. It held at that level in June.
As no president before him had served more than two terms in office, and many political leaders -- even some in his own party -- frowned on breaking that tradition, Roosevelt stayed mum about his re-election plans, waiting until the July 1940 Democratic national convention to be officially nominated. After his death in 1945 during his fourth term, Republicans started the process of amending the Constitution to limit presidents to two elected terms, leading to ratification of the 22nd Amendment in 1951.
These data can be found in Gallup Analytics.
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