<a href="https://en.wikipedia.org/wiki/President-elect_of_the_United_States" id="mwzA" rel="mw:WikiLink" title="President-elect of the United States">President-elect of the United States</a> <a href="https://en.wikipedia.org/wiki/Zachary_Taylor" id="mwzQ" rel="mw:WikiLink" title="Zachary Taylor">Zachary Taylor</a> and Vice President-elect <a href="https://en.wikipedia.org/wiki/Millard_Fillmore" id="mwzg" rel="mw:WikiLink" title="Millard Fillmore">Millard Fillmore</a> did not take their respective oaths of office (<a href="https://en.wikipedia.org/wiki/Inauguration_of_Zachary_Taylor" id="mwzw" rel="mw:WikiLink" title="Inauguration of Zachary Taylor">they did so the following day</a>), leading to the erroneous theory that outgoing <a href="https://en.wikipedia.org/wiki/President_pro_tempore_of_the_United_States_Senate" id="mw0A" rel="mw:WikiLink" title="President pro tempore of the United States Senate">President pro tempore of the United States Senate</a> <a href="https://en.wikipedia.org/wiki/David_Rice_Atchison" id="mw0Q" rel="mw:WikiLink" title="David Rice Atchison">David Rice Atchison</a> had assumed the role of <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Acting_president_of_the_United_States" id="mw0g" rel="mw:WikiLink" title="Acting president of the United States">acting president</a> for one day.