PARIS -- Europe's landmark new constitution faces a make-or-break referendum in France today, when a polarized nation decides whether to boost or block the next giant leap forward in a half-century of efforts to unite the continent.
After months of debate over the merits and drawbacks of the European Union's historic first charter, the complex business of getting 25 countries to agree on an ambitious roadmap for their future hangs on two simple words: "oui" and "non."
The latest poll gave the "no" camp 52 percent support and the "yes" camp 48 percent, meaning the treaty still could face a humiliating defeat in the nation that played a lead role in drafting it.
All 25 EU member states must ratify the constitution before it can take effect in 2006, and a French rejection would be the first in Europe.
A French "yes" -- coupled with improbable approval in another referendum Wednesday in the Netherlands, where opposition is running at about 60 percent -- could give the charter unstoppable momentum as a dozen other nations decide its fate in coming months.
But a defeat here would resonate even more powerfully across the continent. In 1951, two Frenchmen -- Robert Schuman and Jean Monnet -- launched the six-nation European Coal and Steel Community, the precursor to today's EU.
"If we vote 'no,' we may be left out of everything," said Lucien Steinamm, a 23-year-old gardener who is among the more than 20 percent of voters who are undecided.
The possibility that the EU's latest bold attempt to knit together its ragtag club of nations could wind up stillborn had many wondering what might lie ahead.
"If there was to be a French 'no' vote -- a serious big rejection of the treaty -- followed by a rejection in the Netherlands, then I think that this treaty is in effect dead," said John Palmer, an analyst with the European Policy Center in Brussels, Belgium.
"The danger then would be that we would enter a period of profound stagnation, maybe for two, three or more years, until we have new elections in France and some of the other key countries."
Backers say the constitution, which EU leaders signed in October, will streamline EU operations and decision-making, make the bloc more accessible to its 450 million citizens and give it a president and foreign minister so it can speak with one voice in world affairs.
Opponents fear it will strip nations of national identity and sovereignty and trigger an influx of cheap labor just as European powers such as France and Germany struggle mightily to contain double-digit unemployment.
Nine nations -- Austria, Hungary, Italy, Germany, Greece, Lithuania, Slovakia, Slovenia and Spain -- already have ratified the constitution by referendum or parliamentary vote.
About 1.5 million voters in France's overseas territories from Polynesia to the Caribbean cast their ballots Saturday, with the results to be kept under wraps until the end of voting today in mainland France. The government imposed a pre-vote ban on radio, television and Internet campaigning that took effect at midnight Friday and remains in place until polls close at 10 p.m. today.
In Paris, where bitter debate over the charter has so dominated cafe and household chatter that even bakers are selling large France-shaped "oui" and "non" gingerbread cookies, President Jacques Chirac put his government's credibility on the line with an all-out campaign to persuade nearly 42 million sharply divided voters to support the constitution.
"I'm definitely going to vote 'yes.' It's the logical progression in everything we've done since the Treaty of Rome" that formed the embryo of the modern EU in 1963, said Jerome Wyncke, a 33-year-old computer programmer. "I'm for a federation in Europe like in the United States."
But across town, in a gritty cafe near Pere Lachaise, the storied cemetery where famed French playwright Moliere and former Doors frontman Jim Morrison are buried, sales clerk Francoise Foulon wasn't buying.
"I'm for a democratic Europe, but I detest outside meddling. I live in France, not Brussels," she said.
While a defeat would shake the EU to its core, it could plunge France -- one of the architects of the project -- into political chaos. Chirac's popularity ratings have plunged to 39 percent in recent weeks, and there was widespread speculation a "no" would prompt him to fire unpopular Prime Minister Jean-Pierre Raffarin.
If the French reject the treaty, Chirac would suffer the humiliation of becoming only the second leader, after Gen. Charles de Gaulle, to lose a referendum since the founding of the Fifth Republic in 1958.
Opponents, including extreme-right leader Jean-Marie le Pen and Socialist former Prime Minister Laurent Fabius, have suggested the charter could be re-negotiated and altered to suit French tastes. Chirac has shot down that notion, warning that a "no" would mean "Europe would be broken down, searching for an impossible consensus."
Others sought to play down the long-term significance of a rejection.
"A defeat for the constitution would not be the catastrophe that some Europhiles seem to think," The Economist said in an editorial savaging the constitution.
"Life would go on, even in Brussels, and a union that has lasted for almost half a century is surely strong enough to deal with the occasional rebuff from voters."