For more than 100 years, starting with the 1840 presidential election, every president elected in 20 year increments (1860, 1880, 1900, 1920, 1940, and 1960) died in office.  
Curse Broken:  Only with the election of Ronald Reagan in 1980 was the curse broken, and, of course, Reagan almost succumbed to an assassin’s bullet shortly after his inauguration.  George W. Bush, elected in 2000, also escaped the curse.

Here’s a recounting of what happened to our presidents during these 120 years of presidential elections:
1840 – William Henry Harrison:  At the time of his election, Harrison was the oldest man ever elected president.  His very long inaugural address in chilly Washington, DC weather, and his age contributed to his short-lived presidency.  Harrison was the first president to die in office, and also holds the record for the shortest presidential term (one month).
1860 – Abraham Lincoln:  Lincoln was first elected in 1860 and then re-elected in 1864, and became the first president assassinated just over a month into his second term in 1865.  His April 15, 1865 death came just after the end of the Civil War.
1880 – James Garfield:  Just four months into his presidency, Garfield was shot on July 2, 1881 at the train station in Washington, DC.  He lingered for 80 days, eventually dying on September 19, 1881.  With today’s modern medicine, Garfield would likely have survived the attack.
1900 – William McKinley:  Originally elected in 1896, McKinley was re-elected in 1900.  Seven months into his second term, he was assassinated in Buffalo, NY, dying a little over a week later on September 14, 1901.
1920 – Warren Harding:  Mercifully, the string of presidential assassinations abated for a period of time.  Harding, who was the first sitting senator elected to the presidency, died on August 2, 1923 while on a west coast trip.  Harding was not in good health and died of multiple problems including high blood pressure, rupture of a brain artery, pneumonia, enlargement of the heart.
1940 – Franklin D. Roosevelt:  The only president elected to more than two terms, Roosevelt was elected to his third term in 1940 and his fourth term in 1944.  During the 1944 campaign, many close to the president knew that he was a sick man and not likely to make it through another four grueling years as president.  Less than three months into his fourth term, FDR died of a cerebral hemmorage at his cottage in Warm Springs, Georgia.
1960 – John F. Kennedy:  As the youngest man ever elected to the presidency (Theodore Roosevelt was younger than JFK when he became president upon McKinley’s assassination), Kennedy was assassinated in Dallas, Texas on November 22, 1963 while he rode through the streets of Dallas in an open motorcade.
The Future:  Presidential security today is obviously much tighter than in earlier years, and this has contributed to the fact that no president has died of an assassin’s attack in almost a half century.  The health of candidates running for president today is scrutinized much more by the media and the public than in previous years, so hopefully a person elected as president has a strong constitution, enough to withstand the pressures of the presidency that ages even the healthiest of people.
Mike Purdy’s Presidential History Blog 
© 2011 by Michael E. Purdy 
www.PresidentialHistory.com