On the eve of the new year – sticking my neck out is an understatement – I predicted that Mitt Romney would defeat Hillary Clinton for the Presidency. A week ago, it looked as if I would not even have a horse in the race. In this year's contest, the gap between "Can anything stop Obama?" and "Can he possibly recover?" is a few hours polling in a small, frozen, remote state.
Interpretation is almost as hard as prediction. One theory is that Barack Obama's opinion poll lead vanished in the privacy of New Hampshire's polling stations, when a lot of people decided that they could not actually bring themselves to vote for a black man. Then again, an American conservative friend of mine said last weekend that a number of his acquaintances, though well to the right of Mr Obama, were attracted by him.
Here was a black politician who was not in thrall to Jesse Jackson and Al Sharpton; who would not pander to the grievance-obsessed, racially antagonistic blend of aggression and self-pity which often passes for black politics in the US. It is possible that only a black President could finally close the file on slavery, and indeed on the civil rights movement, thus enabling the descendents of America's involuntary immigrants to sign up for their share of the American dream. As a healer and a mover-on, Mr Obama seemed to appeal to a lot of voters who did not share many of his views.
Perhaps there were not enough of them in New Hampshire. But it is also possible that the Granite State was merely living up to its reputation. Its motto is "Live free or die" and most of its inhabitants try to obey that injunction. Yet every four years, they somehow succeed in merging their cussed individualism in a common purpose: confounding predictions and pollsters, enlivening American politics with a good hearty dollop of the unexpected.
Some commentators attribute the turn-up to Hillary's tears, in contrast with Mr Obama's triumphalism. Is that possible? The rugged citizenry of New Hampshire are realistic, tough-minded folk. Could they really have been taken in by that performance? A weeping Hillary: you would need a heart of stone not to laugh.
They know how to ham, those Clintons. A few years ago, Bill arrived at a funeral. He was laughing and joking with his companions, until he saw the TV cameras. Seconds later, a tear trickled down a sombre face. No doubt he has taught his wife how to cry on demand – though we should accept that her tears of rage at his conduct were sincere.
If Mrs Clinton is the candidate, this will cause difficulties for her male opponent. In attack, she will be mean-minded, clawing, spitting, vicious: no blow too low. Under attack, she will react as if every wrong which the female sex has suffered in the course of human history is being re-inflicted upon her. Her appeals to chivalry will outdo the most eloquent antebellum maiden in the Charleston of the 1850s. Small boys are told never to fight with little girls, for two reasons. First, public opinion will be against them. Second, they will lose. A big boy would face similar problems in taking on Hillary. He would just have to hope that enough voters see through her. After all, in the age of chivalry, she would have been burnt as a witch.
There is another uncertainty. Michael Bloomberg has proved to be an outstanding Mayor of New York. He offers competence, at a moment when a lot of Americans feel that it is lacking in Washington. He could spend a billion on a presidential race without falling out of the mega-rich list. He has considered running as an independent, but has no wish to emulate Ross Perot in 1992 or John Anderson in 1980. Mr Bloomberg would only stand if he thought that he had a realistic chance of winning.
An Obama candidacy would probably be the end of his hopes. Mr Obama would sweep up far too many of the "time for a new politics" voters whom Mayor Bloomberg would need. Yet suppose it were Hillary: a damaged Hillary who had limped home by mobilising enough of the Democratic core while reinforcing everyone else's negative impression of her? As it seems inconceivable that any Republican contender will suddenly metamorphose into an unbeatable candidate, Mr Bloomberg might have a once-in-a-lifetime opportunity. Although he would certainly not be a second Anderson or Perot, there would be no guarantee of success. At 30 per cent, he might win nothing, at 40 per cent, everything. But he would be the most formidable third party candidate since Theodore Roosevelt in 1912.
It is interesting to examine the reasons for this. In America, as in Britain, the political system seems solid, in that it has endured in a similar form for many years. In both countries, however, it rests on a far frailer foundation of public consent than most politicians will acknowledge. In the UK, there is evidence for this in the growth of abstentionism and the decline of the two major parties' share of the vote. At the next election, we could have the first properly-hung Parliament since 1929.
In both the US and the UK, the big parties are fortunate to share one advantage: the high cost of entry into a first-past-the-post electoral system. But Mr Bloomberg does not have to worry about costs. Moreover, the American primary system can encourage insurrections within parties. By undermining previous favourites it can also incite third forces. This is one reason why the Republicans and the Democrats entered a tacit conspiracy to defang the primary electorates by compressing the process, in the hope of preventing an insurrection from having enough time to gain momentum. Yet, as this year demonstrates, not all the teeth have gone.
One explanation for the two American parties' weakening hold over the electorate is that they have both become more homogeneous. The Democrats have lost the southern conservatives; the Republicans the north-eastern liberals. In the days when each party was more of a coalition, it was easier to retain the allegiance of potentially discontented voters, who could always identify with something.
Now, however, there are plenty of US citizens who share the Republicans' economic views, and might indeed favour a return to fiscal conservatism, but are uneasy about the influence of the Christian right. There are also Democrat-inclined voters whose aspirations are expressed in the old jingle: "Compassionate at home,/strong overseas/good enough for Roosevelt/good enough for me". Their worry is the anti-Americanism of the Democratic left, who seem to wish to disaggregate the US into a series of battlefields for contending minorities. In both parties, there are a lot of social moderates who dislike culture wars and are nostalgic for the era when "E pluribus unum" was an uncontentious public ethos. Competent government and cultural moderation could be a good basis for a Bloomberg campaign.
This is already the most interesting Presidential race for many years. I will now make a safe prediction. There will be plenty more excitement to come.