Who will succeed George W Bush?

The first votes won't be cast for a year. The big hitters have yet to declare. Yet the biggest, costliest and most unpredictable political circus on the planet is already well under way. Rupert Cornwell profiles the good, the bad and the unlikely in the contest to succeed George W Bush

The suave former Massachusetts governor Mitt Romney appears at a Boston convention centre for a public fundraising extravaganza that nets a cool $6.5m (£3.3m) in a single business day. Democrat Barack Obama appears at a party dinner in New Hampshire, as if he were the second coming. Oh yes, and a supposedly secret internal strategy document of the Rudolph Giuliani campaign appears on the front page of a New York tabloid - courtesy of a source "sympathetic to one of Giuliani's rivals for the White House". Need more be said? The biggest, costliest and most unpredictable political show on the planet is getting under way in earnest.

The first votes that actually count in the struggle to succeed George W Bush will only be cast on 14 January 2008, when Iowa holds its caucuses. But the action is already coming thick and fast, despite the fact that the most important of the expected candidates - Obama and Hillary Clinton for the Democrats, Giuliani and John McCain for the Republicans - have yet to formally declare.

But exploratory committees have been set up, and the all-important financial primary is in full swing. The would-be contenders are sounding out donors and rounding up supporters at dinners in key primary states. They are signing up advisers, writing worthy op-ed pieces, and publishing rousing biographies.

The decision of Republican Romney to have the press witness his online money-gathering spectacular on Monday was no idle gimmick. The former Massachusetts governor knows that the campaign entry fee for a serious candidate may reach $100m. By the time it's all over, and the 44th President of the United States is elected on Tuesday 5 November next year, the whole thing will have cost $1.5bn or more. And between now and then, anything can happen.

For the first time since 1928, no incumbent President or Vice-President is seeking his party's nomination. Come 20 January 2009, America might find itself inaugurating its first black president, its first female president, even (if Romney goes all the way) its first Mormon president. For now, suffice to say, the country may be facing its most turbulent election cycle since 1968.

The next election, the noted Democratic political consultant James Carville has opined, will be "the most exciting and important" in recent history. The pundits always say that, of course, even though the most important recent election - that of 2000 - at the time seemed one of the least consequential and among the dullest, at least until the post-election "hanging chads" saga in Florida. Yet the Gush and Bore (sorry, Bush and Gore) contest brought in its wake Iraq, the polarisation of America at home, an unprecedented dislike of America abroad, and an upheaval in the international order, of which the worst may be yet to come.

But the comparisons with 1968 are striking (assassinations excepted, one prays). Now, as then, America is embroiled in an unpopular war, and led by an unpopular President (with the difference that Bush, unlike Lyndon Johnson, is barred from running again). That election ended 36 years of Democratic dominance; 2008 could end an even longer era of Republican supremacy. Now as then, the limits of American military power abroad have been exposed - but with added uncertainty now about the limits of American economic power, threatened by debt, deficit and fast-growing powers like China and India. According to statistics, the US is becoming more prosperous, but rarely have people worried as much about their jobs, schools, healthcare and general standard of living.

Unsurprisingly, people are fed up with the usual negative, ultra-partisan politics. About the only institution less popular than the President is Congress. Voters took out their frustrations by handing Republicans a stinging defeat in November's mid-term elections - and Democrats at least are sending a similar message with their current love affair with Obama, the young black Senator from Illinois, untested and unproven but with an enticing message of conciliation and national unity. In 2004, the watchword for both parties was "get out the base". This time the spoils of victory will go to whoever wins over independents and the floating centre.

If the electorate is in flux, so are the parties. Democrats have yet to resolve the tug-of-war between Clintonite centrism (of which Clinton, assuming she runs, will be the family standard-bearer in the campaign ahead) and the left-wing populism to be embraced by declared candidate John Edwards - and, who knows, maybe by an Al Gore redux. At least, however, the party is united in opposition to the Republican war in Iraq.

On the other side there is no such clarity. Even without a war, Republicans would be divided - between left and right wings, between social conservatives and libertarians, between old-fashioned budget orthodoxy and the big-government, big-deficit conservatism practised by Bush. Iraq, meanwhile, has reopened the age-old foreign policy divide between realists and idealists, between isolationists and interventionists.

The war poses the biggest personal risk to McCain, the early Republican frontrunner whose unswerving support for the 2003 invasion, and now for the unpopular troop increase ordered by the President, could end up costing him the White House. But a highly unpopular President may be fatal for any Republican candidate.

Not since 1996 have the Democrats gone into an election in so favourable a position. With their mid-term capture of Congress, the party has gained a platform from which to show they can use power responsibly. The issues favour Democrats, too, from the Bush tax cuts that have widened the gulf between rich and poor, to the worries about jobs and healthcare. Iraq has wrecked the Republicans' reputation as the party better able to keep America safe.

Then there is the old principle of Buggins' turn, on the thesis that after eight years of a Republican President, it's time to give a Democrat the chance to run the country.

Most important, however, are signs that demographics and suburbanisation are shifting the underlying balance of power between the parties. The much-touted Republican lock on the electoral college may be coming loose, as Democrats advance inland from the coastal strongholds to which they were largely banished in 2000 and 2004. Next time around, the party could not only regain the eternal swing state of Ohio, but Florida could fall into Democratic hands. A growing Hispanic population gives the Democrats a better shot in places like Arizona and Colorado. Virginia, once rock-solid Republican, is now a swing state. Barring a miraculous turn-around in Iraq, it will be Republicans, not Democrats, who are on the defensive next year.

One thing is certain. The potential 2008 field is one of the strongest in decades. Hillary Clinton starts as the Democratic frontrunner, but she might have to contend with a former Vice-President, Al Gore, as well as both halves of the 2004 Democratic ticket (John Kerry and Edwards) and, in Obama, the most exciting emerging US politician since, well, one Bill Clinton. Apart from McCain and Romney, the Republican field might contain Giuliani, the much-fêted former New York mayor, his successor Michael Bloomberg, and even the former Speaker Newt Gingrich. Whatever this group lacks, it isn't talent.

For what little they are worth (at this stage name recognition is all), early match-up polls tend to show McCain, though not Giuliani, beating Clinton. More striking is the number of senators in the field (probably seven at least) offering a real chance that one of their number could enter the White House for the first time since John Kennedy in 1960. For the rest, look to an old rule: when they choose a president, Americans want the opposite of what went before - even if they are sold a bill of goods in the process.

Jimmy Carter, seen as weak and pessimistic, was followed by the sunny, optimistic Ronald Reagan, who promised "morning in America". Reagan's harsh conservatism was replaced by the "kinder, gentler" Republicanism of George Bush Snr. In 1992 Bush, seen as old, bumbling and out of touch, was overthrown by youthful, touchy-feely Bill Clinton. Eight years later, Bush Jr won, promising straight talk and high moral standards after the slippery, philandering Bill. Now the search is on for Mr or Mrs X to succeed a President perceived as dogmatic, divisive and ignorant.

On the principle of opposites, the winner in 2008 will be flexible, intellectually prepared and able to reach out across party lines. McCain? Maybe, but he's a warrior politician whose strongest suit is not flexibility. For all her talents, Clinton remains a polarising figure. As for Obama, he's the quintessential healer. He also certainly has the brains - but does he have the experience? So maybe the hour of Al Gore, the prophet spurned, has arrived at last, or the hour of Romney with his managerial polish... or... or... The stakes are enormous, and the possibilities are almost endless. Let battle be joined.

Winner takes all: runners and riders for 2008

REPUBLICAN

Rudolph Giuliani

New York's then mayor became "America's Mayor", as he guided his city through the trauma of 9/11. Giuliani is a hawk on the subject of national security but liberal on issues such as abortion rights, gun control and gay civil unions. The conventional wisdom is that he would be formidable in a general election, but could have trouble surviving the primaries, where social and religious conservative voters are crucial. The latter may also have problems with his turbulent marital history, and his links with the scandal-plagued former Police Commissioner of New York Bernard Kerik. Even so, Giuliani runs level with, or even slightly ahead of, McCain in early polls.

John McCain

The Arizona Senator and Vietnam war hero, who gave George W Bush a big scare in 2000, is the man to beat on the Republican side. But his ante-post odds are lengthening slightly. Seven years ago, McCain was the anti-establishment candidate, with his "Straight Talk Express" campaign bus. Though he retains great appeal to independents and potential crossover Democrats, he has subtly become the establishment's man, having made his peace with Bush and the Christian right. McCain's irreverence and his inspiring personal story mask the fact that he is highly conservative on many issues. He has yoked his fate to his support for a war the public is sick of. His age is also a question mark. McCain exudes energy, but he would be 72 on taking office, the oldest President in American history.

Chuck Hagel

One of the most respected foreign policy voices on Capitol Hill, the Nebraska Senator was dubious about the Iraq war even before the invasion. He has sternly criticised President Bush's refusal to face facts on the situation in Iraq and to hold talks with Iran. He has also described as "senseless" the 45-year US embargo against Cuba. None of which endears Hagel to the Republican faithful - or to his old friend and fellow Vietnam veteran John McCain, for whom he campaigned in 2000. On social and domestic issues, however, he is more conservative. A Hagel candidacy would be an intriguing addition to the Republican field - though he's easier to imagine as President than as Republican nominee.

Sam Brownback

Social conservatives could have a genuine one of their own to vote for if Kansas' senior senator enters the fray. The devout Brownback, 50, is a tireless campaigner against abortion, embryonic stem cell research, human cloning, pornography and indecency in broadcasting. A strong supporter of the Iraq war, he has an idealistic yet fiercely nationalist approach to US foreign policy: an expert has called him "closer to George Bush in temperament, vision and faith" than any member of Congress. Unlike the President, however, he has worked closely with individual Democrats on causes close to his heart. Brownback starts as a rank outsider, but could be a threat in southern and Midwestern Republican primaries.

Mitt Romney

Is America ready for a Mormon President? That is the question about the 59-year-old former Governor of Massachusetts, a successful businessman and widely praised organiser of the 2002 Winter Olympics in Salt Lake City. Handsomeand competent, Romney looks the part. He also has an impressive record on healthcare and education in heavily Democratic Massachusetts. Of late, he has shifted to the right, as he seeks to fill a perceived conservative gap in the Republican field. But his religion could count against him. If he runs, it will be exactly 40 years since his father George Romney, three-term Governor of Michigan, sought the Republican nomination, only to bow out before the 1968 New Hampshire primary.

DEMOCRAT

Hillary Clinton

She has it all - the name, the brains, the political talent, the money and the putative campaign team. For extras, she happens to be married to America's sharpest political mind. But many believe that she cannot be elected President - not because she is a woman, but because she is too polarising a figure. In fact, the former First Lady, once derided as a liberal caricature, has remade herself as a centrist and a skilled legislative operator during her six years in the Senate, honing her foreign policy and security credentials. But her initial support for the Iraq war has made her a liability in terms of the left-wing vote, while her husband Bill, too, is a mixed blessing. Not because he isn't popular - but do Americans really want another instalment of the Bill-and-Hillary marital melodrama?

Tom Vilsack

Four of the last five Presidents were once Governors, so don't write off the former two-term Governor of Iowa. Vilsack, 56, was orphaned at birth and later adopted. He is articulate, personable and exudes Midwestern common sense and decency. His politics are from the moderate Bill Clinton wing of the party. The first Democrat to formally enter the race, he knows full well that he is a long shot, even though he could get a flying start in his home state caucuses, which kick off the primary season next January. John Kerry seriously considered him for a running mate in 2004. That could be Vilsack's destiny in 2008.

Al Gore

The world's most famous eco-warrior insists he won't run - but the chink of possibility he and his advisers keep open means that, unless he slams the door shut Sherman-style, Gore has to be considered. He has the name recognition and the clout to enter the campaign relatively late, as well as the significant advantage of having been unequivocally right on two great issues of the day, Iraq and global warming. Alas, Clinton's former Vice-President is as lousy at campaigning as he is good at policy-making. The defect cost him victory against George Bush in 2000. It could doom him again. But no one could say America hadn't been exposed to serious arguments.

John Edwards

Having earned high marks as John Kerry's running mate in 2004, the eternally boyish former North Carolina Senator is making a second push for the top job - and if Hillary and Obama self-destruct, he could come through on the rails. Edwards has honed his populist message. In 2004, he merely denounced the divide between the "Two Americas" - now he offers the specific proposals on healthcare, education and taxation to narrow that divide. Thanks to his 2004 campaign, he has high name-recognition, as well as strong backing from organised labour. Once a top-bracket personal injury lawyer, he can be a compelling speaker.

Barack Obama

Four years ago, only close students of Illinois state politics had heard of him. Today, at 45, this former state legislator and University of Chicago law professor is the hottest political property in America. The son of a Kenyan father and a Kansan mother, he has a silky style that showers sweetness and light on all he surveys. Though he hasn't entered the presidential race yet, Obama has dropped heavy hints that he will run, and is already close behind Hillary in many polls. But he has done next to nothing of significance in his two years in the Senate. If he does throw his hat into the ring, will he quickly be exposed as an empty vessel - or is he the new JFK?