With his presidential nomination wrapped up in record time by last week's southern primaries, Vice-President Al Gore went to Philadelphia to thank his trade union backers. And he warned them, as well he might, that he had a "huge battle" on his hands if he was to defeat the Republican nominee, George W Bush.
"In order to win," he said, "we have got to understand, the other side is going to throw everything they've got, plus the kitchen sink. They're manning the barricades; they're trying to funnel unprecedented amounts of money into the campaign. They're going to stop at nothing."
Current opinion polls show Mr Gore and Mr Bush running neck-and-neck. With the best part of eight months to go until the election, however, most US pundits give the advantage to Mr Gore, citing his lust for the fight, his White House experience and the present, sunny state of the country.
With the stock market up since Mr Clinton took office, unemployment and crime both down, and the world - however uneasily - at peace, the status quo should work in Mr Gore's favour. But eight months is a very long time in electoral politics, and recent days have foreshadowed just how much could go wrong between now and 7 November, and how much is actually out of Mr Gore's hands.
Perverse though it seems, one of the most trivial developments in the global context is also one of the bigger potential threats to Mr Gore's electoral prospects. Petrol prices in the United States are edging up above two dollars a gallon, the highest they have been in dollar terms ever and the highest in real terms for more than a decade.
While Europeans might have scant sympathy for American drivers who have knowingly succumbed to their craving for four-wheel-drive gas-guzzlers and still pay less than half of what most Europeans pay at the pump, the price of gas affects the American mood as little else. The "sky-rocketing" price of petrol is heading the news here.
Well aware of how sensitive the issue could become, President Clinton sent the energy secretary, Bill Richardson to the Gulf to argue for "stabilisation". His low-key return suggested a brush-off and perhaps a reminder from the major oil producers of the free-market principles Washington applies to everything else.
If Gulf producers do not increase production, however, and the price continues to rise, the Administration (and by extension Mr Gore) will be doubly vulnerable. It will have failed to protect America's drivers, and it will have failed to exact due payback for the US having put its troops on the line in the Gulf War. Such charges are already emanating from Republicans, and they could be used against Mr Gore.
Rising petrol prices are already showing through in increased inflation, which could precipitate another feel-bad factor: higher interest rates. The Federal Reserve makes its next decision on rates this week, but it has several more opportunities to adjust rates before November, and each new move has the potential to depress the stock market.
With many more Americans having an interest in stocks and shares even than four years ago, a sharp and sustained fall in share values could cast doubt not only on the Clinton Adminstration's economic stewardship - so far one of its strongest suits - but on the relevance of Mr Gore's experience, which has been in a rising market. At the end of a week that saw extraordinary swings on the traditional and new-tech exchanges, the best that can be said of the markets is that they are exceptionally volatile.
Not all is as predictable as Mr Gore would like in the outside world, either. Two ambitions that Mr Clinton appeared to have within his grasp a few months ago - a Middle East peace agreement and the end of direct British rule in Northern Ireland - are now in suspension and may or may not be back on track by November.
Recent skirmishes in Kosovo have drawn attention to the fragility of peace there; an upsurge in violence, or even the de facto partition of Kosovo along ethnic lines, could call into question the whole rationale of last year's Nato-led (Clinton-led) military intervention. If US soldiers were killed, the wisdom of such troop deployments would bounce back on to the political agenda and probably harm Mr Gore.
To the extent that such untoward events (and a myriad others, as yet unforeseen) could doom Mr Gore by association, they would help Mr Bush, who could add them to the pile of "Clinton-Gore" misjudgements. The Governor of Texas would have to guard against coming across as ignorant or inexperienced himself; he would also need to ensure that he did not transgress the bounds of good taste and national solidarity. But Mr Gore must also beware of the temptation to gloat overmuch about America's current wellbeing, lest it turn around and bite him.