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Consider Herman Cain, whose 2012 rise and abrupt collapse was perhaps the most astonishing boomlet in recent memory. Like Buttigieg, who is a small-city mayor, Cain was an unlikely presidential contender—his major claim to fame was as the head of Godfather’s Pizza, which isn’t even the South Bend, Indiana, of pizza chains. In a way, it feels unfair to compare Buttigieg—a Rhodes Scholar with government experience who has shown a deft grasp of policy details so far—to Cain, whose signature idea was a nonsensical tax plan. On the other hand, it seems unfair to compare Cain to Buttigieg, whose best showing in any poll so far is 4 percent. By contrast, Cain managed to nearly quintuple his share in polls over the course of a single month in the fall of 2011, hitting a high of 26 percent in the RealClearPolitics average. Soon, however, allegations of sexual harassment earlier in Cain’s career surfaced, and soon after he quit the race.

What can we learn from Cain’s boomlet? The first lesson is that little-known candidates are a volatile prospect because, unlike more experienced politicians who have faced the press glare at the national or even state level, they are relatively unvetted. This means that when they’re discovered, they can soar with the attention of a newly interested press. But once their weaknesses are discovered, they can quickly crash.

Another is that Cain’s boomlet, like many in the past, was the fruit of voters turning against something. Cain was just one of a few Republicans to experience a bubble that year, along with former Texas Governor Rick Perry, former Senator Rick Santorum of Pennsylvania, and former House Speaker Newt Gingrich. The reason was that Republican voters that year were cycling through contenders to find someone—anyone—other than Mitt Romney to nominate, before finally realizing that the ex–Massachusetts governor was their best bet. (Though not a winning bet, as it turned out.) Something similar happened in 2004, when retired Army General Wesley Clark briefly made a splash in the Democratic primary. His military résumé made him stand apart from the rest of the Democratic field, until a few weeks of watching his actual campaign showed he was just as hapless as rivals such as then-Senators John Kerry and Joe Lieberman.

But the Buttigieg boomlet is a little different. Buttigieg isn’t really popping up as an alternative to any particular Democrat, because there isn’t a clear front-runner in the race. Former Vice President Joe Biden continues to lead in every poll, but he still hasn’t actually entered the race, and many political analysts consider his numbers to be fragile—especially after two accusations of inappropriate touching against him by women in the past week.

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