President pro tempore of the United States Senate

The president pro tempore of the United States Senate (/ˌproʊ ˈtɛmpəriː/ or /ˌproʊ ˈtɛmpəreɪ/), also president pro tem, is the second-highest-ranking official of the United States Senate. According to the United States Constitution, the Vice President of the United States is ex officio the President of the Senate, despite not being a senator, and the Senate must choose a president pro tempore to act in the Vice President's absence. Since 1890, the most senior senator in the majority party has generally been chosen to be president pro tempore; this tradition has been observed without interruption since 1949.

President pro tempore of the United States Senate

The president pro tempore of the United States Senate (/ˌproʊ ˈtɛmpəriː/ or /ˌproʊ ˈtɛmpəreɪ/), also president pro tem, is the second-highest-ranking official of the United States Senate. According to the United States Constitution, the Vice President of the United States is ex officio the President of the Senate, despite not being a senator, and the Senate must choose a president pro tempore to act in the Vice President's absence. Since 1890, the most senior senator in the majority party has generally been chosen to be president pro tempore; this tradition has been observed without interruption since 1949.