I asked readers before last night’s debate what advice they might give Herman Cain in order to bolster his credibility as a presidential contender. With a debate performance that was momentum-breaking at the very least, that advice could really come in handy about now.

DonKeyhoti offers some very practical counsel: “After tonight’s debate, Cain should sit down with his advisers and list on a single sheet of paper, the topics of immigration, Iraq/Afghanistan wars, European debt crisis, China, health care, Social Security, jobs and the national debt. Next he should develop 3 to 5 bullet points that reflect his positions on these eight issues. These positions should represent his core beliefs. He could then focus his response to questions on these issues so that it will give him a consistent message.”

Others thought Cain’s willingness to swap Gitmo terrorists for a captured American was a fatal error. Jwjsabin argued that “was about as elementary a mistake as could be made. I don’t think he can recover from that.” Eoniii agreed: “That’s the single stupidest, most irresponsible thing I’ve ever heard a national politician say.”

But the most thoughtful response, I think, came from Oldabandonedbeachhouse, who wrote: “First Trump. Then Bachmann. Then Perry. Now Cain. And each time, AFTER he or she had risen to the top spot or two, the question was asked, what can they do now to demonstrate they are legitimate? Shouldn’t the real question be asked of the base, which is why are you supporting a series of charlatans for the most important position in the world?”

Well, I share this reader’s concern that the GOP electorate this time seems to be flitting from one celebrity contender to another, although Texas Gov. Rick Perry had experience but simply failed to perform.

I think a few things are at work. First, we may be expecting a reasoned response from a great number of unserious voters, who are only partially paying attention. They catch a glimpse here or there; they tell a pollster, “Yeah, Cain looks good.” Most voters, at this stage, are evaluating the contenders as TV viewers rate a new series. To their credit they at least recognize when their favorite of the week bombs.

Second, voters don’t want a repeat of 2008, when their candidate couldn’t hold his own in a debate, didn’t have a killer instinct and seemed just too old. So they’ve placed a high premium this time on rhetorical skills. That’s not unreasonable, but they are learning the hard way that style without substance isn’t going to work in a presidential race.

And finally, I think we’ve so lowered the bar for running for president in the post-Obama era that the self-selection that used to restrain the unqualified and ignorant candidates has largely vanished. Never held public office? No problem. Haven’t a clue about national security? No worries. This mentality, some would call arrogance, that anyone regardless of experience can run and govern has thrown a great many marginal candidates into the field. It’s just taking a little while for voters to sift through them.