从1946年以来的74年中，60次是现任总统当选，14次例外，包括2017，18

这才使得奥巴马连任了12年。

In the 74 times Gallup has asked the open-ended most admired man question since 1946, the incumbent president has topped the list 60 times. Harry Truman (1946-1947 and 1950-1952), Lyndon Johnson (1967-1968), Richard Nixon (1973), Gerald Ford (1974-1975), Jimmy Carter (1980), George W. Bush (2008) and Trump (2017-2018) are the incumbent presidents who did not finish first in past years.

When the sitting president is not the top choice, it is usually because he is unpopular politically. That was the case in 2017 and 2018 when Trump had 36% and 40% approval ratings, respectively, and finished second to Obama as most admired man.

https://news.gallup.com/poll/328193/donald-trump-michelle-obama-admired-2020.aspx