Andrew Romano over at Newsweek wrote earlier this week that US presidential hopeful John McCain’s new blog, written by former Weekly Standard blogger Michael Goldfarb, is an entertaining read compared to Barack Obama’s corporate-like campaign blog. To Romano, this indicates that McCain is stuck in “insurgent mode.” “Team McCain has concluded that the only way to stay competitive is to stay lean and ‘human’ and hope that the candidate’s accessibility and charm earns him free coverage,” said Romano.

Nancy Scola over at TechPresident, on the other hand, disagrees. Scola thinks that the Obama campaign simply decided that a fun-to-read campaign blog isn’t a great use of resources. And she might be right — how many people really read blogs, anyway?

While it would be easy to look at McCain’s blog as a runaway success because the posts routinely have thousands of comments (Obama’s posts get hundreds of comments each, but the blog has a higher post volume), there is likely more to it than meets the eye.

A Harris Poll from earlier this year found that 56% of Americans never read political blogs, and just 22% read them several times per month or more. Interestingly, those over the age of 63 were the most likely to be readers of political blogs — just 17-19% of Gen X and Gen Y (called “echo boomers” in the Harris Poll report) read political blogs.

That certainly explains why Obama has eschewed building a conversational blog while McCain has hired a well-known and experienced blogger — Obama appeals to the specific demographic that doesn’t read political blogs, while McCain appeals to the demographic more likely to subscribe to them. But could that speak to a larger trend in the blogosphere as a whole?

Unfortunately, I couldn’t find any recent polling data on how many people are reading blogs. In 2005, comScore found that about 30% of American Internet users read blogs (PDF), though their study didn’t really delve into how often people were reading blogs. Is that 30% who read them every day? Or 30% who have visited a blog in the past year? The study doesn’t make that clear. Very likely, things have changed since 2005 — when the comScore report was published, for example, TechCrunch — now one of the world’s largest blogs — was only 2 months old.

However, if the Harris Poll data is at all representative of the mainstream public’s reading habits toward blogs in general, things don’t look particularly rosy. The Harris Poll found that of those who visit at least one political blog at least one time each week, 76% read under four of them — a third read just one. So even though blog readership may be up, people are reading only a small number of blogs on a regular basis.

Further, 69% of political blog readers don’t comment on blogs. That indicates that those thousands of comments on McCain’s blog are coming from a small subset of political junkies who closely track the political blogosphere. And that makes sense anecdotally. I have a number of friends who are political and tech junkies and consume tens or hundreds of blogs daily and comment on them regularly. But I have an even greater number of friends who are average, mainstream web users. They may read blogs once in awhile — but generally only in topics they are very interested in (i.e., even though they might be casually interested in politics, and read political news that pops up on their MyYahoo! page, or watch it on TV, they’d never think to read DailyKos or Little Green Footballs unless specifically pointed there).

Fellow ReadWriteWeb blogger Sarah Perez has observed the same thing with her friends, who might occasionally read an industry blog or visit ICanHasCheezBurger, but generally don’t regularly consume blogs every day. So really, just how mainstream are blogs? If avid blog readers tend to be those who are deeply passionate about a subject, and if most of the mainstream’s interactions with blogs are on a limited basis, it could be that blog reading is still a very niche activity. What do you see anecdotally from your non-geek friends? Do you know of any recent studies into blog readership that we’ve overlooked? Let us know in the comments.

Image via factoryjoe.