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.
2016 United States presidential election in Iowa
Following his second term, President Obama is not eligible for another re-election. In October 2015, Obama's running-mate and two-term Vice President Biden decided not to enter the race for the Democratic presidential nomination either. With their term expiring on January 20, 2017, the electorate is asked to elect a new president, the 45th president and 48th vice president of the United States, respectively.