Yesterday, both President Bill Clinton and his Republican challenger, Bob Dole, obeyed the Labor Day tradition: the incumbent taking to the hustings in the key industrial state of Wisconsin, and his opponent off to a rally in St Louis at the 600ft high arch on the banks of the Mississippi river, symbolic gateway to the West and (Mr Dole fervently hopes) gateway to the swing state of Missouri and to final victory on 5 November.
For both men it is the last election, hard though that may be to believe of that compulsive and hugely gifted campaigner Bill Clinton, at the tender political age of 50. As for Mr Dole, at the age of 73 he has, in his own words, "nowhere to go but the White House, or home".
And it is to the latter that the Republican presently looks to be heading. Mr Clinton starts with all the high cards, and every precedent argues for his re-election. For one thing, incumbents who avoid a serious challenge in the primaries invariably win. So do those presiding over an economy growing - as did the US's in the second quarter - at 4.8 per cent a year.
Polls since last week's convention in Chicago put his lead back at 15 to 20 per cent, virtually eradicating whatever "bounce" Mr Dole took with him from San Diego a fortnight ago. Never in modern American history has such a deficit at Labor Day been reversed in the following two months.
Admittedly, Gerald Ford in 1976 and Hubert Humphrey in 1968 came close after emerging from their respective conventions far behind. But both failed. And even in the most legendary comeback of them all, Harry Truman's against Thomas Dewey in 1948, the largest measured lead of the Republican was 13 per cent. And Truman was an incumbent president.
To turn history on its head, the conventional wisdom says, Mr Dole must have some help from outside - a Wall Street crash (unlikely), a foreign policy calamity (Iraq thus far is not measuring up), or a scandal that engulfs Mr Clinton (despite Whitewater and Dick Morris, nothing in prospect of the scale required).
In terms of regions, and the individual states whose electoral college votes formally determine the winner, Mr Clinton's position looks equally unassailable. On both coasts he is far ahead: in the East, he is poised to carry every state from Maine to Maryland, with the possible exception of New Hampshire. On the other side, Washington, Oregon and above all California, whose 54 electoral votes are, on their own, one-fifth of the 270 needed to win, look solid.
Mr Dole can count on most of the South, although Mr Clinton should win in at least his native Arkansas, perhaps Tennessee, and is competitive in Florida which no Republican can afford to lose. Almost certainly, Mr Dole will carry the central tier of Plains states, north and south of his native Kansas, as well as most of the Rocky Mountain states.
And if the race does become close, it will be decided in the arc of old industrial states from Wisconsin through Illinois, Ohio and Michigan to Pennsylvania - in every one of which the President now enjoys a handsome lead. If the election were held tomorrow, one study says, he would win an electoral college landslide of 409 to 126.
The presence, too, of the independent Ross Perot works to Mr Clinton's advantage. The Texas billionaire has yet to find a vice-presidential candidate for the Reform Party ticket, and his first 30-minute television "info- mercial" this weekend went by almost unnoticed. But even if he wins half or less of the 19 per cent he took in 1992, the bulk of those votes are expected to be at Mr Dole's expense.
Mr Perot's strongest issue is the deficit, and, in Sunday's broadcast, he took direct aim at Mr Dole's promise of a 15 per cent across-the-board tax cut, describing it as a re-run of the supply-side "voodoo economics" of the Reagan era, which had helped run up the national debt to $5,000bn (pounds 3,300bn).
Small wonder the Dole camp is desperately trying to keep Mr Perot out of the three presidential debates this autumn, the first of them in St Louis on 25 September, and that Mr Clinton's aides are trying equally hard to have him take part.