Elected to the U.S. Congress in 1948, in 1954 became the youngest majority leader in its history at the age of 46. He led the condemnation of Senator Joe McCarthy, and later, in 1960, lost the fight for the Presidential nomination. Name this person.

This Texan's political ascent was notably swift. After serving in the House of Representatives since 1937, Lyndon B. Johnson won a fiercely contested and controversial election to the Senate in 1948 by a mere 87 votes, earning him the nickname "Landslide Lyndon". Once in the Senate, he quickly moved up the leadership ladder, becoming the Democratic Whip in 1951 and the Minority Leader in 1953. By 1955, when the Democrats regained control of the Senate, Johnson became the youngest majority leader in the chamber's history. He was renowned for his powers of persuasion, a method famously dubbed the "Johnson Treatment".

As majority leader, Johnson was a pivotal figure in the legislative landscape of the 1950s. During the height of the Red Scare, he was the Democratic leader when the Senate moved to censure Senator Joseph McCarthy in 1954 for his reckless accusations and abusive tactics. Johnson played a key role in guiding major legislation, including the Civil Rights Act of 1957. His ambition eventually led him to seek the presidency in 1960, where he entered the race for the Democratic nomination. However, he ultimately lost to the youthful Massachusetts senator, John F. Kennedy.

Despite this defeat, Johnson's political journey was far from over. In a surprising move, Kennedy chose Johnson as his running mate, hoping the Texan senator would appeal to Southern voters. The Kennedy-Johnson ticket won the general election, and Johnson became Vice President. Following President Kennedy's assassination in November 1963, Johnson assumed the presidency, going on to champion his "Great Society" domestic programs and landmark civil rights legislation from the White House.