Smith was a candidate for the Republican nomination in the 1964 presidential election; she was the first woman to be placed in nomination for the presidency at a major party's convention. Upon leaving office, she was the longest-serving female Senator in history, a distinction that was not surpassed until January 5, 2011, when Senator Barbara Mikulski was sworn in for a fifth term. Smith was ranked as the longest-serving Republican woman in the Senate, a distinction that was not surpassed until January 3, 2021, when Susan Collins, who holds the same Senate seat she previously held, was sworn in for a fifth term.