With polls showing voters swinging between "yes" and "no" - with treaty opponents holding a narrow lead this week - a rerun of 1992, when the French approved the Maastricht treaty by only 51 percent, is possible.
So says an AP report covered by The Guardian website, which also cites French prime minister Jean-Pierre Raffarin saying: "Every vote will count."
Certainly, the French political élites are showing increasing desperation and so, it seems, are the Germans, according to a story in the Canadian daily, the Globe and Mail.
This paper reports how French citizens who thought they would spend a quiet day at the Louvre this week have found themselves assaulted by German youths, dozens of them, intent on plying them with blue-and-yellow flags, heaps of literature and long, impassioned arguments.
It cites Hans-Stefan Stemmer, a 20-year-old Berlin university student, who tells a bewildered elderly couple in fluent French in the museum’s elegant courtyard, "I'm asking you, as fellow Europeans, to think about whether you want my people to retreat back into our old history." They decline his offer of European Union flags, but say they will think about about his entreaties.
Mr. Stemmer, it seems, and hundreds of his comrades are part of a desperate last-ditch effort this week by leaders across Europe to persuade the French to vote in favour of adopting the constitution.
Since nothing seems to have worked, it was time to bring in the Germans. The students have been bussed from across Germany to beg and plead on French streets for people to cast a "oui" vote, in the belief that French citizens, suddenly disillusioned with their media and politicians, are more likely to listen to rank outsiders.
However, the sub-test of the approach is, to say the least, sinister, if not alarming. A "retreat back into our old history" from a German can only really mean one thing, the message effectively being – if you take it to its logical conclusion – "vote 'yes' or we'll invade France – again".