Mr Goldwater, 89, who had a stroke in 1996, was said to have Alzheimer's.
Elected to the Senate in 1952, he gave up his seat for the 1964 presidential bid he lost to Lyndon Johnson. He returned to the Senate in 1968.
In 1974 Mr Goldwater told President Richard Nixon he faced imminent impeachment amid the Watergate scandal; Nixon subsequently resigned.
Mr Goldwater retired in 1986 after serving five terms.Reuse content