President-elect
From Tardis Wiki, the free Doctor Who reference
The President-elect was the title given to an individual elected as president, but not yet sworn into power. (TV: The Invasion of Time)
The Seventh Doctor once introduced himself as "President-elect of the High Council of Time Lords, Keeper of the Legacy of Rassilon, Defender of the Laws of Time, Protector of Gallifrey". (TV: Remembrance of the Daleks)
When meeting the Toclafane in 2008, Arthur Coleman Winters introduced himself as President-elect of the United States of America. (TV: The Sound of Drums)