Firstly, these predictions are all the result of statistical or arithmetic projections of polls we know to be flawed in many ways.  These flaws include:

1. Under-representation of cell-phone only voters - this is known to skew opinion polls by as much as 2-4% against Obama.

2. Early voting trends have been heavily skewed in favour of Democrats - a vote in the bag is worth a lot more than a "likely voter" who may be put off by long voting lines or other priorities on voting day.

3. Obama's superior ground game - and the much greater enthusiasm/determination being exhibited by his supporters - obvious in the long lines that have formed at early voting and now election day voting places.  At the end of the day - even with an unprecedentedly high turnout - perhaps some 30% of the electorate will fail to vote - and these are much more likely to be over-representative of the more lukewarm and disinterested voters or those who do not have the support of a GOTV operation.  Its much easier to state a preference to an online or telephone pollster than it is to actually go out and vote.

4. The "likely voter" models some pollsters use to screen their results are still often based on the historically lower turnouts amongst minority and youth voters - something which does not appear to be reflective of the early voting patterns to date.

However is it not also possible that we might be seeing a "Shy Obama Supporter effect" amongst voters who do not wish to attract the ire of their traditionally conservative friends, relatives and neighbours?  These are "soft" questions, which the polls, by definition, cannot answer, because they all posit some form of voter dissonance between what they say they will do, and what they actually end up doing.  These are questions which a commentator from afar such as I simply cannot answer at this stage except to say that I remain a skeptic that they will end up having a significant aggregate effect either way.

Many pollsters and commentators much closer to the action and more experienced than I seem to be hedging their bets on these factors, and purport to see a "tightening" in the polls as polling day approached.  This tightening is certainly visible in the latest pollster.com table:

What is striking is that the 9 closest states from Virginia down to Georgia have all trended towards McCain in the last day, and all except the last 3 have also been doing so over the past week. However the national trend has been towards Obama over the same periods and so what we are seeing here is specific to those states, and not to the US as a whole. If there was significantly heightened anxiety about an Obama Presidency, would we not see it reflected in the national polls?

Far more likely we are seeing the effects of the heightened campaign and media focus on those battleground states and the distortions noted in paras. 1-4 above.  In other words I will stick my neck out and project a 10%+ margin of victory for Obama (based on a c. 3% net anti-Obama polling bias for reasons 1-4 above) and a 396/142 Electoral College win for Obama based on his winning all the states in the table above right down as far as the last "toss-up" state of Georgia.

Of course for statistical noise reasons alone, it is far more likely that Obama will lose at least one of those "toss-up" states - Montana and North Dakota seem the most likely because there have been far less polls there and so the confidence levels associated with any prediction has to be a lot less. But equally,on that basis, Obama might even pull off a really stunning upset - such as in McCain's home state of Arizona - if he really does achieve a 10%+ lead in the national popular vote.  

So at the risk of looking very foolish I will go with my instincts and predict a 10%+ margin of Victory for Obama with an absolute and extraordinary 396/142 blow out margin in the Electoral college.  At that rate the Democrats also stand at least a 50:50 chance of securing a 60:40 filibuster proof margin in the Senate and we could be seeing the dawning of a new age in American and World Politics.

Obama already has the 270 EVs he needs if he wins all the states (down to Pennsylvania) classified as strong Dem in the table above, and 291 if he takes the "Lean Dem" states of Nevada and Virginia as well.  Virginia should be one of the earlier states to declare a result (provided the long voting lines don't result in some delayed vote counts).  If Obama wins Virginia he should be safe.  Otherwise we could be in for a long night and many days in court before this thing is finally resolved.

Update [2008-11-5 2:50:55 by Frank Schnittger]: Well Obama did win Virginia and did win the race early by a blow-out margin. The final popular vote tally won't be in for some time, but it looks like being some way short of the 10%+ I predicted. I suspect that this was mostly because the turnout was unprecedentedly high on both sides - with the Republicans also getting their vote out despite an inferior ground operation.

In terms of electoral college votes it is looking like 375/163 rather than the 396/142 I predicted, but still within the generally accepted definition of a blow-out which I used in the poll. The variance with my forecast being due to Georgia (15), Montana (3), and North Dakota (3). Of these Georgia was always the long shot at the bottom of the list of toss-up possibilities. Montana and North Dakota were the most difficult to predict (as noted above) because of the relative paucity of polls there. At the time of writing, Missouri is to close to call, but seems to be trending towards Obama, and so I have included it in his numbers. It looks like it could be decided by a few hundred votes. Thankfully it isn't the decisive state, as otherwise the Supreme Court would have chosen the next President again.

I used the ad breaks on CNN to look at some of the Fox news coverage. Hardly ever having viewed it before, I was astonished at how dull and unimaginative it was. I was expecting a much slicker presentation and some more poisonous comment. They seemed to be taking defeat lying down. Why would even wingers watch this stuff? All the commentators seemed to agree that Obama ran a near flawless campaign with an unprecedented ground game, use of new technology, management and message discipline, and an eloquence to match the Kennedys and Martin Luther King. His only miss-steps were cited as his "bitter" comment and perhaps a delay in disassociating himself from the Rev. Wright. When even your detractors find so little to criticise, you must have run one hell of a campaign.

I thought both McCain's and Obama's speeches were very good. Neither even mentioned George W. Bush - a suitably ignominious end to an illegal regime. McCain was gracious in defeat - to a degree which seemed to disconcert his supporters. Obama wisely focused on the challenges ahead. His, will be a short honeymoon, and any triumphalism now would be used against him when the first set-backs come - as they inevitably will. He also, wisely, shared ownership of victory with his supporters, and offered it to his opponents. He will need the support of a broad coalition to overcome the challenges ahead.

PS Helen wins the stiff drink(s) for the most accurate prediction. The prize couldn't go to a more deserving person! Please name your tipple, Helen! [END UPDATE]