Why do pols make fools of themselves so often? Mostly because they're human, plus two things: they have cameras following them around, and opponents who have an incentive to dig out things that most of us are able to keep hidden.
Of course, most of us haven't cheated on our spouses, or embellished our resumes, or done anything else that would look bad if people knew about it. Right? Uh, anyone still here?
Well, there's also the whole motive, means, and opportunity thing. On cheating...not only are they (often) rich and (what passes for) powerful, which from what I hear helps on the opportunity side, but the business of having two residences with the spouse only present at one of them certainly is a major plus on the means side. My guess? I'm confident that a lot more ballplayers cheat than do pols, who probably are around the rates of corporate CEOs. CEOs don't get in the newspaper when they get caught, however, unless something truly ugly happens. Remember: we hear about pretty much every single Member of Congress who gets caught cheating.
As for embellishing their life stories...I think that one is harder for most people to understand than the cheating thing. Think of it this way. People in job interviews are always advised to put the best light on everything they've done, while making sure to stay clear of going over the line and actually saying something that isn't true. Pols are, among other things, salespeople who are constantly selling themselves; their lives are perpetual job interview. It doesn't surprise me at all that they sometimes get it wrong. From what I've seen so far from the Blumenthal story, it doesn't appear that he's just a flat-out fabulist or scam artist, like this guy; it sounds more like a case of a carefully rehearsed sales pitch that he tweaks this way or that to fit the occasion, and sometimes veers off and winds up in the wrong place. You know, like the way that you can see that your product is good for you, or that it's been recommended by doctors, or that studies have shown that it might be a good defense against X, the condition that causes disease Y...but you can't say that your product cures disease Y.
No, for me what's harder to understand is something like this: Michele Bachmann, Member of Congress, hanging out with the birther crowd (and in this case, the queen of the birthers). Granted, I'm bitter at Bachmann because she didn't fulfill my prediction about her. Still, that she "pals around" (as Alex Pareene nicely puts it) with those even more dedicated to the crazy than herself is, well, a little nuts. Silly pols.
Oh, and the cure for moping about pols? If you think they're all depressing, I recommend this (via Sides).