Johnson won election to the United States Senate from Texas in 1948 after winning the Democratic Party's nomination by an extremely narrow margin with fraudulent votes that were manufactured by friendly political machines. He was appointed to the position of Senate Majority Whip in 1951. He became the Senate Minority Leader in 1953 and the Senate Majority Leader in 1955. Nixon was elected to succeed him, as the New Deal coalition that had dominated presidential politics for 36 years collapsed. After he left office in January 1969, Johnson returned to his Texas ranch, where he died of a heart attack at age 64, on January 22, 1973. In 1937, after the death of thirteen-term Congressman James P. Buchanan, Johnson successfully campaigned in a special election for Texas's 10th congressional district, that covered Austin and the surrounding hill country. He ran on a New Deal platform and was effectively aided by his wife.