In matters presidential, Republicans tend to like things nice and tidy. Democrats, on the other hand, deep down, seem to prefer a mess. And that is just what they have got in this thrilling, deadlocked and utterly unpredictable race for the party's 2008 nomination.
On Tuesday, John McCain made official what has been evident for a month – that he will carry the Republican banner in the 4 November election. But Hillary Clinton's primary wins in Texas and Ohio mean her struggle with Barack Obama will continue for weeks, maybe months, possibly into a bruising showdown at the Democratic Party's Denver convention in late August.
No matter which candidate prevailed, that would be the worst imaginable kick-off for the general election against Mr McCain barely two months later. But how to get out of it?
The neatest solution would be a "dream ticket" combining both the party's superstar candidates. "Why not?" implore many Democratic activists, horrified by the prospect of further warfare between two gifted candidates, in all likelihood turning nastier by the week, making ultimate reconciliation ever harder.
Yesterday, Mrs Clinton seemed to hold out that prospect. "That may be where this is headed," she said on one morning news show after her famous night before. Then, however, came the kicker: "But, of course, we have to decide who's on top of the ticket."
That decision will not be reached with a simple smile and handshake, in the finest traditions of Corinthian sportsmanship. The presidency is the biggest prize of all. Having fought so hard, and having recovered from two near-death experiences – first with her shock victory in New Hampshire and now with her big wins on Tuesday, Mrs Clinton will not slip quietly into the night.
Nor should she. Witness Mike Huckabee's pursuit of the Republican nomination. That he had no chance of winning the race has long been clear. But he did not formally bow out of it until Tuesday night, when Mr McCain mathematically secured the 1,191 delegates needed to win.
So why should Mrs Clinton stand aside when she trails Senator Obama by a mere 80 to 100 delegates (precise counts vary) out of the 2,800-odd allocated or pledged so far? In the 16 remaining contests, only 611 delegates are at stake. Barring a cataclysmic event, neither will reach the finish line of 2,025 without the aid of the 795 super-delegates – most of them party officials or office-holders not designated by primaries or caucuses. Some have pledged to a candidate, others have not. All are free to change their minds at any point.
As the Obama camp points out, by the same token of proportional delegate allocation it is equally all-but-certain that he will lead in the delegate count, even when the last primary votes are counted in Puerto Rico on 7 June. In that case, Obama spin-doctors argue, the super-delegates should accept numerical reality and spare the party a convention bloodbath by closing ranks behind him.
But numbers are only part of the story. Mrs Clinton has a different narrative. Twice she has been written off and twice she has proved the prophets wrong. Belatedly she has got into her stride, finding arguments – experience, trade policy and so on – which have thrown the hitherto masterful Obama campaign off-balance.
Not only is she winning again; this week's exit poll, which found that people who had made up their minds in the last few days went heavily for her, suggests that the momentum of the campaign may have shifted. Belatedly, the media is taking a hard and critical look at the young Illinois Senator. Maybe some voters are having buyers' remorse.
These alone are ample reason and more for her to stay in the race. What also must worry super-delegates and many others is the pattern of results thus far. Barring Mr Obama's home state, Mrs Clinton has won every single "mega-state" contested. Those are the most populous states, with the greatest numbers of electoral college votes, that will determine the outcome in November.
To be fair, primaries are not general elections – and in some of them (Texas for instance) she has only narrowly prevailed. But, as Mrs Clinton noted, no Democrat who has lost the party's Ohio primary has ever won the presidency. Thus, and rightly, the epic struggle goes on. But, with every passing day, the stakes get higher, and the real beneficiary becomes more obvious – John McCain.
Going negative has undoubtedly helped Mrs Clinton, above all the "red telephone at 3am" ad that attacks her opponent for lack of experience. But the ploy is not new. A virtually identical one was used in 1984 by the former Vice-President Walter Mondale against the charismatic upstart Gary Hart (read Barack Obama now). The 1984 Democratic race was the last to be decided by super-delegates, and the "experience" argument may have prodded them to swing to Mr Mondale before the convention, allowing him a smooth send-off for the general election. But victory brought him up against Ronald Reagan, a proven incumbent president, in an "experience" argument he could not win.
If Mrs Clinton wins, she will find herself facing a much-decorated Vietnam war hero, a national security hawk with all the expertise acquired in 22 years in the Senate. If she loses the nomination, she will merely have been doing Mr McCain's job for him, softening up the rookie Obama for the "experience" onslaught he will undoubtedly face from the Republican attack machine.
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