Is foot-in-mouth disease always fatal to campaigns?

Texas Gov. Rick Perry had his “oops” moment on a Michigan debate stage.

Rep. Michele Bachmann (R-Minn.) mixed up actor John Wayne with serial killer John Wayne Gacy.

And Herman Cain referred to “Ubeki-beki-beki-stan-stan.”

The 2012 Republican presidential campaign has provided a bounty of infelicitous phrasings, wrongheaded assertions and embarrassing gaffes.

There was Perry’s memory lapse on the debate stage, which came to be known as his “oops moment.”

There was Bachmann in Waterloo, Iowa, trumpeting her pride at hailing from the same hometown as John Wayne, only to learn that her homie was serial killer John Wayne Gacy. John Wayne, the actor, was born in Winterset, about three hours away.

Now comes Mitt Romney senior advisor Eric Fehrnstrom, who compared his candidate’s conservative positions in the primary to a child’s erasable art toy.

“I think you hit a reset button for the fall campaign,” Fehrnstrom told CNN on Wednesday. “Everything changes. It’s almost like an Etch A Sketch. You can kind of shake it up and restart all over again.”

With that flippant remark, Fehrnstrom gave credence to a deeply held suspicion among some conservatives that Romney is politically inauthentic — that he’ll change positions as easily as a child makes a new drawing.

But will it hurt him in the long run? Probably not.

Gaffes that inflict lasting damage involve more than poor word choices. They are boneheaded misstatements (as when President Ford insisted during a 1976 debate with Jimmy Carter that Eastern Europe was not under Soviet domination). Or they are slips that crystallize something voters feel or sense about a candidate — lack of readiness for the job at hand, incompetence, inauthenticity, snobbery or disdain for average Americans.

“Fehrnstrom’s comments put a fresh headline on an old argument,” said former Republican political strategist Dan Schnur, director of the Jesse M. Unruh Institute of Politics at USC. “There is already a suspicion among a lot of voters that Romney is not entirely consistent in his policy views. So a quote like this from a Romney spokesman is going to have more of an impact than if he had said the same thing on behalf of another candidate.”

But because it did not come from the candidate himself, the sting will probably soon fade.

“If one of Barack Obama’s advisors had talked about working-class voters clinging to guns and religion, we would have long since forgotten about it,” Schnur said, referring to a comment then-candidate Obama made about Pennsylvania’s white rural voters at a private fundraiser in San Francisco in 2008. “If Romney had made the Etch A Sketch comment, it would have dogged him for the rest of the campaign.”

(Notably, Hillary Rodham Clinton creamed Obama in Pennsylvania, especially among white rural voters.)

When Obama said in 2008 that he’d visited 57 states, most people knew he’d made a slip of the tongue. But earlier, when he complained in Iowa about the price of arugula at Whole Foods, he inflicted a wound that never fully healed, reinforcing a sense in some quarters that he was an Ivy League elitist.

Every campaign brings moments the candidates wish they could take back.

Democratic candidate Michael S. Dukakis reinforced an impression of dorkiness in 1988 when he strapped on a helmet and was photographed poking his head out of a tank. President George H.W. Bush conveyed blue-blooded boredom by checking his watch during a debate with Democrat Bill Clinton in 1992. Democrat Howard Dean yelled in a most unpresidential manner after losing the Iowa caucuses in 2004. In September 2008, Republican presidential nominee John McCain asserted that the “fundamentals of our economy are strong” as the country’s banks, auto industry and housing market were collapsing.

Though some gaffes take awhile to seep into the popular culture, the potential for humiliation is instantaneous. Perry’s staff, for instance, knew immediately that their candidate was in trouble for forgetting the third department — Energy — that he had vowed to eliminate.

“Your instincts just tell you, ‘Oh my gosh, this is really bad,’” said Robert Haus, the Iowa Republican strategist who ran Perry’s campaign in that state. “And so you just die inside for the guy.”

Fehrnstrom’s remark fueled a frenzy of Twitter and Internet wit.

“This is such a complete gaffe, it’s almost tidy,” said the writer Michael Kinsley.

Kinsley famously defined a gaffe as “when a politician tells the truth.” He said he came up with that definition during the 1984 Democratic presidential primary, when Gary Hart made a crack about New Jersey. With Hart’s wife at his side, Hart said, “The good news for her is that she campaigns in California while I campaign in New Jersey.”

Self-inflicted wounds are far more dire than those inflicted by advisors, who, after all, can be reassigned. “I have never seen a spokesperson get fired for being overly glib. Thankfully,” said Schnur, a spokesman for McCain in his first presidential campaign.

Fehrnstrom may be guilty of “a poor choice of words,” Haus said. “But everybody is human, everybody is fallible. Everybody needs to get over it.”

Fehrnstrom seems to be doing just that.

On Thursday, he alluded to the controversy in a tongue-in-cheek tweet of his own: “Etch A Sketch stock is up? Psst, I’ll mention Mr. Potato Head next. Buy Hasbro.”