Meh... I think you're projecting here on the base fear of not "jinxing" ourselves. It's really hard to imagine a race-changing moment given how flawlessly O's campaign has been run for the last year.

"...or there is a sudden shift of a couple of hundred undecided superdelegates"

That's funny... the SDs have not shifted suddenly since the campaign began so it's not going to happen any time soon, short of HRC stepping down.

Focus on the trends: O starts 20 points behind HRC in the polls, then within 2 weeks of a given election ramps up efforts in a given state and overtakes HRC. No reason to believe that won't happen in TX, or to think OH will be no blowout for HRC.

Worrying about an unpredictable national security incident that is out of the control of any of the candidates is just another irrational worry. It's possible, but nothing worth spending a lot of time speculating about.

O does not gloat much on the trail, and certainly not enough to turn his likability numbers down. Relax, sit back, and hope HRC does the right thing on March 5.

I don't know that I agree with your overconfidence theory in general. I define overconfidence as an individual's belief that they have/are/will perform better than facts/circumstances would indicate. The O campaign has been careful, when O begins campaigning in a new state, to warn supporters that the nomination is not a done deal and that they have to get to the polls to ensure that voters do not assume it's OK to hang back, given O's lead. The campaign knows that voters can become complacent in the face of success and addresses it directly.

I have not seen the campaign acting in a way that demostrates their belief that they are doing better than the evidence suggests. O has good reason to be confident because of past successes. Polling for the final 3 "big states" are also cause for confidence. Overconfidence would be evidenced by the O campaign declaring they will win OH, TX and PA. But they haven't done that, either for purposes of spin or because they believe it will happen.

As to unforced errors, what evidence suggests O or his campaign are prone to them? (Weren't there allegations of overconfidence right after NH, referring to the interval after IA? I don't recall the basis for those allegations, so I'd like to understand what was implied about overconfidence at that time). What's interesting is the idea that O could come up with something, after more than a year campaigning, that could turn the race, by virtue of huge media spin and the subject of right wing attacks. There's justification to be worried about a not-so-bad gaffe that turns into something huge by virtue of the media. But as an O supporter I think I have a very good idea of the kind of man he is and feel very good about his policy ideas and I have difficulty imagining him coming up with anything that would have a game-changing impact. Of course, I've already made up my mind, so the worry has to be for the undecideds.

Now, with respect to the GE, all bets are off. Not that O would be overconfident, but we just can't say how the Repubs are going to attack and spin. But let's not get ahead of ourselves. ;-)