The Literary Digest Poll was a widely respected poll at the time, but it famously predicted that Thomas Dewey would win the election by a landslide. Truman's victory was a major upset, and the poll's failure led to its demise.

The Gallup Poll was founded in 1935, and its first major success was predicting the outcome of the 1936 presidential election. The poll correctly predicted that Franklin D. Roosevelt would win by a landslide, and it has been a respected polling organization ever since.

The Roper Poll was founded in 1934, and it was the first poll to use a probability sample of the population. This means that every person in the population had an equal chance of being selected for the poll, which made the results more accurate and reliable.

The Gallup Poll correctly predicted that John F. Kennedy would win the 1960 presidential election. The poll showed Kennedy with a slight lead over Nixon in the weeks leading up to the election, and he ultimately won by a narrow margin.

The Literary Digest Poll was the first poll to use a national sample of the population. The poll was conducted by mailing questionnaires to a large number of people across the country. The results of the poll were often used to predict the outcome of presidential elections.

The Gallup Poll correctly predicted that Ronald Reagan would win the 1980 presidential election. The poll showed Reagan with a large lead over Carter in the weeks leading up to the election, and he ultimately won by a landslide.

The Roper Poll was the first poll to use a random sample of the population. This means that every person in the population had an equal chance of being selected for the poll, which made the results more accurate and reliable.

The Gallup Poll correctly predicted that Bill Clinton would win the 1992 presidential election. The poll showed Clinton with a slight lead over Bush and Perot in the weeks leading up to the election, and he ultimately won by a narrow margin.

The Roper Poll was the first poll to use a stratified sample of the population. This means that the population was divided into different groups, such as age, race, and gender, and then a random sample was taken from each group. This ensured that the poll was representative of the entire population.

The Gallup Poll correctly predicted that George W. Bush would win the 2000 presidential election. The poll showed Bush with a slight lead over Gore in the weeks leading up to the election, and he ultimately won by a narrow margin.

The Gallup Poll was the first poll to use a multi-stage sample of the population. This means that the population was divided into different stages, such as counties, cities, and blocks, and then a random sample was taken from each stage. This ensured that the poll was representative of the entire population.

The Gallup Poll correctly predicted that Barack Obama would win the 2008 presidential election. The poll showed Obama with a large lead over McCain in the weeks leading up to the election, and he ultimately won by a landslide.

The Roper Poll was the first poll to use a panel design. This means that the same people were interviewed multiple times over a period of time. This allowed the pollsters to track changes in public opinion over time.

The Gallup Poll correctly predicted that Donald Trump would win the 2016 presidential election. The poll showed Trump with a slight lead over Clinton in the weeks leading up to the election, and he ultimately won by a narrow margin.

The Gallup Poll was the first poll to use a computer-assisted telephone interviewing (CATI) system. This system allowed interviewers to enter data directly into a computer, which made the polling process more efficient and accurate.