Abraham Lincoln, Franklin D. Roosevelt and George Washington are most often the three highest rated presidents among historians. The remaining places in the top 10 are often rounded out by Theodore Roosevelt, Thomas Jefferson, Harry S. Truman, Woodrow Wilson, Dwight D. Eisenhower, Andrew Jackson and John F. Kennedy. More recent presidents such as Ronald Reagan and Bill Clinton are often rated among the greatest in world opinion polls, but do not always rank as highly among presidential scholars and historians. The bottom 10 often include James Buchanan, Warren G. Harding, Andrew Johnson, Franklin Pierce, Millard Fillmore, William Henry Harrison, John Tyler, Ulysses S. Grant, Zachary Taylor, and George W. Bush. Because William Henry Harrison (30 days) and James A. Garfield (200 days, incapacitated after 119 days) both died shortly after taking office, they are sometimes omitted from presidential rankings. Zachary Taylor also died after serving as president for only 16 months, but he is usually included. In the case of these three, it is not clear if they received low rankings due to their actions as president, or because each was president for such a limited time that it is not possible to assess them more thoroughly.
Political scientist Walter Dean Burnham noted the "dichotomous or schizoid profiles" of presidents, which can make some hard to classify. Historian Alan Brinkley stated that "there are presidents who could be considered both failures and great or near great (for example, Nixon)". Historian and political scientist James MacGregor Burns observed of Nixon: "How can one evaluate such an idiosyncratic president, so brilliant and so morally lacking?".
David H. Donald, noted biographer of Abraham Lincoln, relates that when he met John F. Kennedy in 1961, Kennedy voiced his deep dissatisfaction and resentment with historians who had rated some of his predecessors. Kennedy said: "No one has a right to grade a President—even poor James Buchanan—who has not sat in his chair, examined the mail and information that came across his desk, and learned why he made his decisions".
Historian and political scientist Julian E. Zelizer argues that traditional presidential rankings explain little concerning actual presidential history and that they are "weak mechanisms for evaluating what has taken place in the White House". Libertarian political commentator Ivan Eland wrote a book titled Recarving Rushmore (2008; updated 2014), in which he wrote that historians' criteria are poor in their capacity to reflect presidents' actual services to the country. In the book, Eland chose to rate 40 U.S. presidents on the basis of whether their policies promoted prosperity, liberty and non-interventionism as well as modest executive roles for themselves—his final rankings varied significantly from those of most scholars.
The 1948 poll was conducted by historian Arthur M. Schlesinger Sr. of Harvard University. The 1962 survey was also conducted by Schlesinger, who surveyed 75 historians. Schlesinger's son Arthur M. Schlesinger Jr., conducted another poll in 1996.