A far trickier problem, however, are the actual ballots. And it's that process, separate from the nominating process, where time is running out. In the U.S., each individual state controls the election process, from making and printing ballots, to counting votes on Election Day, to certifying election results.
Election law in the U.S. is a 50-state patchwork. From voting machines to filing deadlines, each state has different rules. And it's the printed ballots—and even early voting that has already begun—that concern party officials should Trump quit. The closer it gets to the November election, the more state ballots will have Trump's name on them, as state deadlines for certifying nominees' names have come and gone.
It's already impossible, in fact, to keep Trump off all 50. Most state deadlines to certify names for the ballot passed in September or early October, meaning that even if Trump quits today you'll still be able to vote for him in many states.
The Electoral College provides additional sources of potential mayhem. Electors in most states are party officials, loyalists who have pledged to vote for their party's nominee should they win a majority of that state's votes. But should state party officials rebel, the national party would have little recourse to stop it. State parties could, in theory, nominate a different candidate for president, or make their electors unpledged, meaning that they are obligated to vote for no one.
George Wallace, left, attempting to block the integration of the University of Alabama in 1963. (Photo: Public domain)
This has happened only a handful of times in modern political history, most recently in 1964, when George Wallace, a Democrat from Alabama, ran against the incumbent President Lyndon B. Johnson. That year, Democratic party officials in Alabama opted to make their electors unpledged, and Johnson's name simply didn't appear on ballots across the state. Instead, voters chose between Barry Goldwater, the Republican nominee, and the unpledged electors, in effect handing the state to Goldwater, though Johnson won the election handily.
The system is designed to handle sudden jolts, in other words, even if the jolt is often a sign of a broader dysfunction within the country or a particular campaign. The results rarely turn out well.
When Eagleton stepped down in 1972 he was replaced by Sargent Shriver, an in-law of the Kennedys and the father of Maria Shriver. McGovern and Shriver went on to lose in November to the incumbent President Nixon and Vice President Spiro T. Agnew, in what was then the biggest landslide in modern political history.
Update, 10/8: This story has been revised to reflect new developments.