THIS year's US presidential campaign, unlike the previous one four years ago, is almost devoid of inspiration. In 2008, Barack Obama's message of change and hope infused energy into a broad coalition of liberals, young people, women, and ethnic minorities. If Republicans could muster nothing comparable, they at least had a bona-fide war hero as their candidate. And their vice-presidential nominee, Sarah Palin, had her enthusiastic supporters, as well as a range of appalled critics.

This time around, President Obama finds himself dragged down by a struggling economy and unfulfilled promises. He can justly claim to have kept the recession from becoming much worse, but the economy is still not thriving. He succeeded in transforming our defective system of medical insurance, but the new law has yet to come into effect. It falls short of the single-payer plan that many liberals were hoping for, and, at this point, seems to be creating as much anxiety as confidence among the people that it is meant to help.

In international affairs, President Obama completed the withdrawal from Iraq, but actually reversed his promised direction in Afghanistan, initiating a large troop build-up that has accomplished little. His commitment to end the legal morass of indefinite detention for accused terrorists at Guantanamo has come to nothing. He has also done little to ameliorate inequities in our immigration policies. His one significant gesture to the Left has been in the area of gay/lesbian rights, which also happen to enjoy increasing support from the public at large.

In all these respects, his liberal supporters have found him less than satisfactory. Part of his difficulty has been that he tried to create a less partisan atmosphere in Washington. By definition, this requires co-operation from both sides, and Republican resistance, more entrenched than ever, has defeated him. All told, President Obama's accomplishments have neither matched his promise nor helped to solidify the coalition that elected him.

HIS Republican opponent may be in not too different a position. Mitt Romney has won his party's nomination, but is dogged by a wooden personality and a continuing suspicion that he does not really stand for anything. This, to be sure, was the only kind of candidate that the Republican Party could field, given its internal incoherence. The main necessity was that the candidate should pacify all elements, without really identifying with any.

The Republican Party is still, as it has been for generations, the party of big business, as witness the immense amounts of corporate money pouring into the campaign. But there is also a long history of Republican libertarians - Senator Barry Goldwater was a notable example - who primarily want to reduce government "interference" in private life.

They would like to see a reduction in taxes and in social entitlements, although many of them, paradoxically, insist on their right to Social Security and Medicare in retirement. Many libertarians also oppose legislation limiting access to abortion or prohibiting same-sex marriage, which they see as unwarranted government interference in private life.

THIS stance puts libertarians in conflict with another group of Republicans, the "Christian Right", a significant element in the party since the time of Ronald Reagan, which has succeeded in making these issues important planks in the party platform. Its central concern was an effort to reverse what it saw as a dilution of American morals, exemplified in the increasing independence of women, the legality of abortion, and the newly public presence of gay men and lesbians.

Also, the most recent round of congressional elections, in 2010, was the background to the rise of the "Tea Party", an amorphous group that combined fiscal interests like those of the libertarians with opposition to abortion and same-sex marriage.

In the mean time, old-fashioned "moderate" Republicans have largely disappeared. These were fiscal conservatives - advocates of balanced budgets, and supporters of business. But they were not doctrinaire. They were willing to negotiate with their opponents, and they were not entirely hostile to the safety net of social welfare which grew up during and after the 1930s.

Libertarians cannot manage much enthusiasm for a candidate who embraces the principles of the Christian Right - and vice versa. The Tea Party combines elements of both, but is too small to swing the election by itself.

Business interests are uncomfortable with the radicalism, fiscal and social, of more doctrinaire conservatives, although they still hope to dominate the party themselves. Romney may be closer, at heart, to the old "moderate" Republicans than to any other group. But, since they have largely been forced offstage, he finds himself appealing to other, conflicting perspectives.

DEMOCRATS, then, are left to vote in hope that a second Obama administration will accomplish more than the first, while Republicans will have to base their vote more on loyalty to a deeply divided party than on any kind of inspiration coming from the candidate. Meanwhile, the increasing number of voters who decline to declare a party identification will be the deciding factor. At this point, they seem likely to favour whichever side they find less alarming.

Whatever happens this year, President Obama's election in 2008 created a new historic era. It replaced one great barrier in American culture with fresh possibility. But this great event, borne on a swell of popular inspiration, has yet to realise its promise in the actual business of governing.

The Revd Dr Bill Countryman is Professor Emeritus of New Testament at the Church Divinity School of the Pacific in Berkeley, California.