Twenty-second Amendment to the United States Constitution
The amendment prohibits any individual who has been elected president twice from being elected again. Under the amendment, an individual who fills an unexpired presidential term lasting greater than two years is also prohibited from winning election as president more than once. Scholars debate whether the amendment prohibits affected individuals from succeeding to the presidency under any circumstances or whether it only applies to presidential elections.
2020 United States presidential election
Beginning in August 2017, reports arose that members of the Republican Party were preparing a "shadow campaign" against Trump, particularly from the moderate or establishment wings of the party. Now late Arizona Senator John McCain said that "[Republicans] see weakness in this president." Maine Senator Susan Collins, Kentucky Senator Rand Paul, and former New Jersey Governor Chris Christie all expressed doubts in 2017 that Trump will be the 2020 nominee, with Collins stating "it's too difficult to say." Senator Jeff Flake claimed in 2017 that Trump is "inviting" a primary challenger by the way he is governing. Longtime political strategist Roger Stone, however, predicted in May 2018 that Trump may not seek a second term if he succeeds in keeping all of his campaign promises and "makes America great again".