James Earl Carter Jr. (born October 1, 1924) is an American politician, philanthropist, and former farmer who served as the 39th president of the United States from 1977 to 1981. In response to the invasion, Carter escalated the Cold War when he ended détente, imposed a grain embargo against the Soviets, enunciated the Carter Doctrine, and led a 1980 Summer Olympics boycott in Moscow. In 1980, Carter faced a challenge from Senator Ted Kennedy in the primaries, but he won re-nomination at the 1980 Democratic National Convention. Carter lost the general election to Republican nominee Ronald Reagan in an electoral landslide. Carter lost the general election to Republican nominee Ronald Reagan in an electoral landslide. Polls of historians and political scientists usually rank Carter as an average president; he often receives more positive evaluations for his post-presidential work. The race for Georgia's 3rd congressional district in 1966 was shaken up in mid-May when the incumbent, Bo Callaway, dropped out and decided to run for Governor of Georgia instead.