Former US Vice President Walter Mondale has died in Minneapolis on Monday aged 93, his family has announced.
Mr Mondale was Jimmy Carter's running mate for his winning 1976 presidential bid and defeat four years later.
Mr Carter said he considered Mr Mondale the "best vice president in our country's history".
That gave him 13 electoral votes compared with President Reagan's record-high tally of 525.
Mr Mondale is also remembered for choosing Geraldine Ferraro of New York as his running mate - the first woman on a major-party presidential ticket.
In a statement, Mr Carter said he was "an invaluable partner and an able servant of the people of Minnesota, the United States and the world".
"Rosalynn and I join all Americans in giving thanks for his exemplary life, and we extend our deepest condolences to his family," he added.
"It is with profound sadness that we share news that our beloved dad passed away," a family statement said.
In the statement, Mr Mondale's family paid tribute to his achievements in housing, civil rights and environmental policy.
They said plans for memorials in both Minnesota and Washington DC would be announced later.