Should we take Herman Cain seriously? The question is not as simple as it might seem. The more precise question is: How seriously we should take him.

He’s already turned in some charming and forceful debate performances. One of the high points of the debate season was his explanation as to why he might not have survived cancer had Obamacare been in effect.

His strong performances, like Mike Huckabee’s efforts in 2008, have been rewarded with movement in the national polls. He also pulled off an upset straw poll victory in Florida. Should he continue on this trajectory, he will become a significant drain on Texas Gov. Rick Perry’s base of support among Tea Partyers and social conservatives.

As Fred Barnes explains, Cain is a smiling presence in a sea of angry voices at these debates:

“I see parallels between the situation that existed at Godfather’s when I came on board and the state of our Union today,” he writes. Obama is “in denial,” Cain says. “He’s a weak leader, his economic policies have failed, and he’s been inconsistent on foreign policy.” Cain “will do what I did when I helped restore Godfather’s Pizza.” That means conservative policies and the tenacity to see them through.

His upbringing may explain his gift for delivering a conservative message with a friendly face, as Ronald Reagan did. “I also like to smile, laugh and have fun with people,” he says. Obama is lugubrious. He lectures. He gives excuses. His speeches are anything but fun.

The Hill reports that Perry’s position is already weakening in Iowa, which may be adding to Cain’s growing support there. Some of that is attributable to social conservatives’ discontent with Perry. (“Former Iowa Republican Party Political Director Craig Robinson said that when Perry entered the race, ‘a lot of Iowans saw him as a more mainstream conservative candidate that could win the nomination, and there were a lot of social conservatives who were ready to go to the Perry campaign.’ But some of Perry’s comments during the debates ‘have given social conservatives in Iowa heartburn,’ Robinson said.”) But part of the erosion in Perry’s standing is no doubt attributable to the realization that at least at this stage in the primary process, there are many options, including Cain, for Christian conservatives.

Cain poses another challenge to Perry, and for that matter, Mitt Romney. There are plenty of reasons to doubt Cain’s 9-9-9 plan (9 percent percent income tax, 9 percent sales tax and 9 percent business tax.) For one thing, once a national sales tax is instituted it comes very easy to push upward. For another, unless there are generous exemptions for food and other necessities, middle- and low-income taxpayers could take quite a hit. And it’s not clear how much revenue it would raise. All of that said, at least Cain has a plan. The two front-runners have themes (cut taxes and spending), but neither has set forth specific plans for tax and entitlement reform. In his book Romney throws out a number of good suggestions for entitlement reform but doesn’t pick one. And in the campaign he’s done a fine job of revealing Perry’s ideas to be both extreme and bizarre (return Social Security to the states?), but he still lacks his own definitive plan. The other candidates might take a page from Cain’s book and put forth some detailed proposals of their own.

So if Cain continues along this route and can show some understanding of a wider range of issues (e.g., foreign policy) he will continue to gain traction and make the going harder for those candidates (Michele Bachmann, Rick Santorum and Perry) who simply must win Iowa.

But could Cain win the nomination? I find that, still, entirely improbable. While business acumen is a good thing for a post-Obama president, many voters don’t think the first tour in public service should be conducted from the White House. We’ve had a president for almost three years who doesn’t work with Congress, lacks competency to formulate legislative proposals and gets trampled by international adversaries as a novice. Republicans aren’t likely to pull the equivalent mistake by selecting a political rookie.

Moreover, Cain at times has shown a shocking lack of appreciation for basic constitutional principles, including the bar on religious tests for office. His idea for privatization of Social Security may, in a time of extreme market volatility, be as controversial as Perry’s idea to send it back to the states. The potential for mega-gaffes and revealing moments of unpreparedness for high office will only intensify as he draws more attention.

Others will point to his lack of money and organization. But these things follow confidence that the candidate is capable of winning the nomination and prepared to govern. Cain, in that regard, has a long way to go.