Race for the White House: It's still a long and very winding road

How will the party finally choose its standard-bearer in the US presidential poll, and then – even more critically – rally behind that candidate? Rupert Cornwell explores all scenarios and identifies the kingmakers

Clinton is expected to lose heavily in North Carolina (AP)

You thought it was complicated? It's getting worse. Last week's win by Hillary Clinton in the Democratic primary in Pennsylvania could have been calibrated by a Republican god to maximise her party's discomfort: large enough to keep her in the race and raise fresh doubts about Barack Obama, but too small to break the deadlock, let alone give her an obvious path to the nomination. Now the action moves west and south, to Indiana and North Carolina in nine days' time – and with good prospect of more of the same.

The votes that really matter now are not the 28 million already cast in this epic struggle, or the six million or so that may be in the nine primaries that remain. Nor are they even the 2.3 million cast in January's "rogue" primaries in Michigan and Florida, voided by the party because they were held too early. Having easily won both, Clinton now desperately wants them to count, to make the case that she, not Obama, leads in the popular vote.

After 18 months of campaigning, and four months' of primaries and caucuses across more than 40 states, the two candidates are divided by just 134 delegates. Yes, Obama leads and remains clear favourite for the nomination. But even he cannot nail down victory without support from the 300 "super-delegates" or party elders, who have yet to make up their minds. Despite his lacklustre performance in Pennsylvania, they continue to trickle to his side. But until the trickle becomes a flood, Clinton will not give in. Herewith, a guide to the tortuous weeks, maybe months ahead.

When is the earliest a winner might emerge?

Conceivably, the party could be put out of its misery by the results in North Carolina and Indiana. In the former, where over a third of registered Democrats are black, Clinton is expected to lose heavily. Indiana, however, is shaping up as the latest make-or-break moment. A mix of city and country, of old industry and new, it's the one "heartland state" left on the calendar, where the candidates are currently neck-and-neck in the polls. If Obama pulls off a convincing double on 6 May, even the infinitely resilient Clinton may read the writing on the wall – especially if previously uncommitted super-delegates cascade to Obama. More prosaically, she may run out of money as fundraisers decide that she no longer has any hope.

Yes, she vows to stay in the race until the convention, come what may. But no candidate in history has publicly admitted they will quit until the moment they announce they are doing just that. On the other hand, suppose 6 May proves a banner night, in which she runs close to Obama in North Carolina and wins solidly in Indiana. She would have even stronger grounds to ask wavering super-delegates to stay their hands.

So what if Indiana and North Carolina don't do the trick?

At the least, Democrats would then have to wait until the primary season ends with votes in Montana and South Dakota on 3 June. The final seven contests, including heavily Hispanic Puerto Rico and the two Appalachian states of West Virginia and Kentucky, on balance favour Clinton. But, remember, it is mathematically impossible for either her or Obama to reach the 2,025-delegate winning post without super-delegates.

What might happen then?

June is the next, and most likely, moment for an orderly denouement. At this stage, Obama would still be firm favourite. Most projections are that, taking pledged delegates and declared super-delegates together, he would finish with more than 1,900 delegates and need barely 100 more to win. Clinton, by contrast, would still be well over 200 short.

Democratic Party chairman Howard Dean has said he wants all uncommitted super-delegates to declare before 1 July, in order to leave the party a couple of months to close ranks and focus its fire on Republican John McCain before the convention in Denver in the last week of August. Dean's writ alone does not run far. But Nancy Pelosi, the House Speaker, and Senate Majority Leader Harry Reid, the two most powerful Democrats on Capitol Hill, feel the same way. Reid appears to be on the fence, but the Speaker has dropped clear hints she supports Obama.

This would be a perfect moment for John Edwards (once upon a time the third member of the "top tier" of Democratic contenders) to break silence and endorse either Clinton or Obama. It would be an equally perfect moment for Al Gore – the most coveted and influential super-delegate of them all – to play deus ex machina. Like Edwards, Gore has not tipped his hand. But there is little love lost between him and the Clintons, and he is widely thought to favour Obama.

Even then, much soul-searching could remain for undecided super-delegates. Suppose Clinton ends the primary season on a winning streak, while Obama commits more "gaffes" and other Jeremiah Wrights pop up from his past? Barring utter calamity, Obama will emerge from the primaries having won the most states, the most pledged delegates and the largest share of the valid popular vote.

"Which super-delegate wants to ignore the will of the people, or to oppose either the first black or the first woman with a serious chance of winning the presidency?" asks Michael Barone, author and senior fellow at the American Enterprise Institute here. "Ideally, they would like to rubber-stamp a choice made by others." The problem is that Clinton is doing her utmost to blur that choice, by insisting on the legitimacy of Florida and Michigan.

But super-delegates also want the Democrat with the best chance of winning to be doing battle with John McCain in the autumn. Thus both the Obama and Clinton camps are bombarding waverers with lists of states where their candidate offers an edge. Barone, for what it's worth, reckons Obama is a better bet in 11 states with 81 electoral college votes, including Nevada, New Mexico, Iowa and Virginia, all carried by President Bush in 2004. But Clinton, he says, would be stronger against McCain in the crucial swing states of Florida, Michigan, Ohio and Pennsylvania (at least two of which Obama would have to win, under almost any scenario, to capture the White House). She might also do better than Obama in Arkansas, West Virginia and Missouri, which went Republican four years ago. Just seven states, but with 107 electoral college votes.

So if the struggle drags on into the summer?

The simplest answer is the dream ticket, Obama/Clinton or Clinton/Obama. This would defuse a growing worry for the party – the large numbers of Clinton and Obama supporters (a quarter in the case of the former) who say they will not vote, or will vote for John McCain, if their candidate is not the nominee.

Alas, the simplest answer isn't really simple at all. On Friday, Pelosi became the latest Democratic grandee to oppose the dream ticket, arguing the eventual nominee should be free to choose his or her running mate. Personalities also militate against the dream ticket. It's well-nigh impossible to imagine Clinton, having long given the impression the nomination was a family entitlement, being content to play second fiddle. You can argue that a stint as Vice-President might be no bad thing for Obama, who will surely have opportunities aplenty to run for President later. But (barring the unlikely event that as first spouse he enters a monastery) what about Bill? To paraphrase the late Diana, Princess of Wales, a Clinton/Obama political marriage isn't big enough for three. In all but name, Hillary's Vice-President would be her husband.

So what then?

At this point, the unthinkable would become inevitable. To repeat, the strong likelihood is that the super-delegates will decide the outcome well beforehand. And even if Denver opens with the contest still unresolved, the delegates would have one last chance of voting a candidate over the top before matters get truly ugly. Some have speculated that a bloc of super-delegates might deliberately abstain, denying either Obama or Clinton a majority and opening the way for a compromise candidate (ie Al Gore).

But that is what Italians call fanta-politica. Far more probable is a brawl, centred on the disputed delegations from Florida and Michigan. Various arcane formulae have been floated. But if none works, and the Clinton camp tries to seat the two delegations regardless, there will be backroom deals and disputatious late-night sessions – a dream come true for reporters, but a nightmare for party managers.

Conventions tend to be minutely choreographed party political broadcasts, from which uncertainty has been stripped, for good reason. The messier the fight – Ford versus Reagan in 1976 among Republicans, Jimmy Carter against Ted Kennedy for the Democratic crown four years later, and the shambolic Democratic gatherings of Chicago 1968 and Miami Beach 1972 – the more likely is defeat in the general election. Dean, Reid and Pelosi are well aware of history. That is why they will move heaven and earth to make sure it doesn't repeat itself in 2008.

The players

1. Howard Dean, party chairman

2. Harry Reid, Senate Majority Leader

3. Nancy Pelosi, Speaker

4. John Edwards, ex-candidate

5. Al Gore, former vice-president

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