The increasingly likely Kamala Harris–versus–Donald Trump presidential contest would be one for the history books. There’s never been anything exactly like it, to be clear. Trump’s three consecutive presidential nominations are pretty unusual, having happened just twice before (with Grover Cleveland, from 1884 to 1892, and FDR, from 1932 to 1944). And Harris represents a whole batch of unusual distinctions. She will be the first Black woman or Asian-American to win a presidential nomination and just the second Black nominee or woman nominee. Beyond that, she’s the first Democrat from California, or even a western state, to head up a national ticket (California Republicans John C. Fremont, Herbert Hoover, Richard Nixon, and Ronald Reagan won presidential nominations, along with fellow westerner Barry Goldwater of Arizona).
None of these factors necessarily has a decisive bearing on the outcome of a Harris-Trump contest. But one distinction Harris possesses is absolutely unique: She is a late substitution for an unpopular Democratic president facing an unpopular former Republican president. Democrats hope this means she can free herself of some of the anchors weighing down Biden’s candidacy (most obviously his age and frailty, but perhaps also his unsuccessful high-profile involvement in the war in Gaza) while offering a fresh contrast with the 45th president. As vice-president during Biden’s term, with prior service in the U.S. Senate and as attorney general of California, she passes any basic qualification test. Indeed, her résumé offers some interesting comparisons like my colleague Jonathan Chait’s characterization of the general election as a battle between “the cop and the criminal.”
Historically speaking, serving as vice-president has been a very common prerequisite for winning a presidential nomination (14 have done so) and for becoming president, either through succession on the death or resignation of a president (eight) or via their own election (seven). Five sitting vice-presidents have been their party’s presidential nominees with two winning (Martin Van Buren in 1836 and George H.W. Bush in 1988) and the other three coming very close (Richard Nixon in 1960, Hubert Humphrey in 1968, and Al Gore in 2000).
If you had to choose an analog for Harris’s current situation, it would probably be Hubert Humphrey’s in 1968. He had served as Lyndon Johnson’s loyal vice-president for one term. Like Biden, though significantly earlier in the year (March 31 as opposed to July 21), LBJ ended his reelection campaign under pressure but on his own terms. Like Biden, LBJ’s job-approval ratings were not good (LBJ’s approval rating per Gallup in late July 1968 was 40 percent). Like Harris, Humphrey did not enter any primaries (though they were far less ubiquitous in 1968). And like Trump, Humphrey’s opponent Richard Nixon was a universally familiar figure with at best mixed popularity. There was a significant non-major-party candidate in 1968 (George Wallace) as there is this year (Robert F. Kennedy Jr.).
After Nixon’s nomination signaled the home stretch of the general-election campaign in 1968, the Republican began with a sizable lead in the limited public polling of that era: Gallup had Nixon leading Humphrey by 16 points on August 21, by 12 points on September 11, then by 15 points on September 29. The very next day, Humphrey made a nationally televised address in which he called for a bombing halt in Vietnam and began a steady ascent in the polls. While Nixon wound up winning the presidency with a lead of 110 votes in the Electoral College, he won the popular vote by just 0.7 percent or about 500,000 votes.
It’s safe to say that today’s Democrats are more united than those of 1968, now that Biden has withdrawn from the race. And Nixon in 1968 wasn’t remotely as controversial as Trump is today. So you have to figure that from a historical perspective, Kamala Harris has good odds of beating Trump if she runs a strong campaign and Trump stays Trumpy.