McGovern was deeply unpopular within certain quarters of his own party, but there’s another reason nobody wanted to serve on his ticket: Richard Nixon. Strange as it may sound today, Nixon was a popular incumbent in the summer of 1972. His approval rating hovered above 60 percent for most of the year, higher than Barack Obama or George W. Bush ever achieved in the fourth year of their presidencies. Since the 1950s, every president who has reached 60 percent approval in a reelection year has won in November.

A strong electoral map only reinforced Nixon’s advantage. After the Democrats backed the Civil Rights Act, Republicans broke through in the South and dominated presidential elections for the next quarter century. From 1968 to 1992, Democrats won just one presidential election, when in 1976 Jimmy Carter triumphed over Gerald Ford, the unelected president who immolated his election odds by pardoning one Richard Milhous Nixon.

While today’s Electoral College advantages Republicans, Democrats in 2020 are fighting on more even terrain than they were in 1972. The country has moved to the left on a host of issues that McGovern championed, including gay rights, health care, and income support for poor workers. And Hispanic and black voters, who broke hard for McGovern, account for a larger share of the electorate.