Phil Klein of the American Spectator asks a question that isn’t pleasant for conservatives to hear, but that we ought to contemplate anyway:

During this election cycle, conservatives have consistently underestimated Barack Obama. There have been numerous occasions in which Obama said things that conservatives were convinced would be damaging, even fatal, to his campaign, and so far they have been proven wrong every time. When Obama said in the YouTube debate he would meet with a rogues gallery of foreign leaders, many conservatives thought he shot himself in the foot, but he turned the uproar to his advantage; when the Jeremiah Wright controversy broke out, many conservatives predicted it could finish him, but there’s not much evidence it did anything other than cause a short-lived dip in the polls; and most recently, many conservatives, including myself, believed that his elitist remarks in San Francisco would damage him, but so far there isn’t conclusive evidence to suggest it has.

We may be past the era of the ‘killer gaffe’ –and it’s worth noting that past killer gaffes were rarely devastating at the time, and only irreconcilably associated with the speaker in hindsight – “I voted for it before I voted against it,” global test, “I took the initiative in creating the Internet”, Dukakis riding in the tank, his emotionless reaction to a question that hypothetically suggested his wife was raped and murdered, etc.

Come to think of it, what gaffe, story, or scandal has been fatal for any candidate this cycle?

For John Edwards, there were few, if any, truly memorable gaffes this cycle, other than perhaps his $400 haircut. In the end, he failed to win the nomination less because of his haircut or his big house or speaking fees, but mostly because he was up against two “superstar” candidates, each making history in their own way in a party obsessed with identity politics.

Team Obama must be looking at Hillary like she’s as hard to finish off as Rasputin. One of the thing that’s still a little surprising to Hillary critics is that the Tuzla Dash ended up being the broadside to her campaign, rather than anything Bill said, or her shifting accents, or her flip-flopping on driver’s licenses, or her claims to central roles in peace in Ireland or her crying in New Hampshire, or her claims to victimhood. Obama-ites can’t believe she claimed lobbyists represent real people. Norman Hsu. Her comparison of Martin Luther King’s role in comparison to LBJ and the importance of Washington insiders. But she’s still here, fighting on, and with at least some chance of winning the nomination…

It’s hard to find any of the Republican candidates who imploded because of one statement or mental breakdown. Rudy Giuliani’s long, slow slide was perhaps triggered by the story about his security detail and his then-mistress, but in the end what appears to have doomed him was being irrelevant to the “who’s going to win” storyline until Florida.

Mitt Romney didn’t implode; he just kept falling short of what he needed – a few percent short of winning Iowa, a few percent short of winning New Hampshire, a few percent short in Florida, and then little or nothing breaking his way in on Super Tuesday. Ana Marie Cox’s list of Romney’s ten worst gaffes, assembled in 2007, is strikingly irrelevant to why he fell short of the nomination — except for maybe the one about hunting. (I thought calling Battlefield Earth one of his favorite movies was weird, but again, in hindsight, nearly entirely irrelevant.)

Huckabee? His question to the New York Times reporter about Mormon beliefs probably spurred some to no longer give him the benefit of the doubt in some areas. He botched a fact or two about Pakistan after Bhutto’s assassination. An unidentified adviser sneering at Rush Limbaugh as part of the New York-D.C. axis didn’t help. But in the end, Huckabee fell short because he had phenomenal appeal to one demographic, evangelicals, and very limited appeal to other ones, just as important to the GOP nomination. He had to win some state that showed he had broader appeal, and it just never came together for him.

Fred Thompson? In a way, Thompson may have had the closest to the “killer gaffe” moments, but it was errors of omission, not commission. He faded into the background on some debates, flopped in front of some audiences, and just never seemed to catch fire. With the Thompson campaign, his fans kept waiting for something to happen… and it didn’t happen in Iowa, was never set to happen in New Hampshire, didn’t happen in Michigan. And when he couldn’t get it to happen in South Carolina, he quickly concluded it wasn’t going to happen.

If John McCain can recover from cosponsoring an immigration reform bill that much of the base saw as amnesty, perhaps we shouldn’t be shocked if Barack Obama escapes unscathed from suggesting small-town Pennsylvanians are embittered gun-owning God-fearing racist xenophobic trade opponents.

So we shouldn’t expect Obama’s poll numbers to suddenly tank. Those who have latched on to him by now are not going to be easily dislodged from his base of support; they can excuse and explain away a great deal.

But whether all of these gaffes, scandals, and revelations can eventually come together to form an unflattering, and defining portrait of the man… well, that’s another question.