Recent polls, however, have shown Le Pen winning between 13 percent and 14 percent in a presidential election. He has built a national organization with dozens of local offices all across France; a substantial number of National Front members have already been elected to municipal and regional government councils. In southern cities, where there exists a potentially explosive combination of large Arab communities and French returnees from the former North African colonies, National Front candidates got as much as a third of the popular vote in the legislative balloting in March 1986. In those elections, Le Pen led a group of 35 of his party's members to seats in the French National Assembly.

The most important factor of the Le Pen phenemonon may well be that the other conservative parties are already worrying that they will not be able to win in next year's presidential elections - thereby achieving their cherished objective of dislodging the Socialists - without Le Pen's help, an alliance they have refused to consider in the past. In the southern city of Grasse, the Mayor, Herve de Fontmichel, was re-elected this summer when he entered into an alliance with National Front members of his city council - prompting his expulsion from the small, centrist Radical Party he had belonged to for most of his career. Other areas are likely to see the same arrangement. And so, when one of Le Pen's closest associates in the National Front, Jean-Pierre Stirbois, told summer audiences that ''every major political figure in France is now forced to define himself in relationship to Jean-Marie Le Pen,'' few stood up to dispute the assertion.

''I don't think that the National Front in itself is the real danger, because, in one form or another, the tendency it represents has always existed in French society,'' said Jean-Francois Kahn, editor of L'Evenement du Jeudi, a leftist weekly magazine strongly opposed to Le Pen. ''The real danger is that the classic conservative parties will ally themselves with the National Front, that Le Pen will make a conquest of the classic right from the inside.''

WHO IS THIS stout, ruddy, roustabout with a glass eye (replacing an earlier pirate's black eyepatch) who called one journalistic critic a ''stinking hyena'' and who foments the message that France is threatened with extinction and only he can save it? The words commonly heard in France to describe Le Pen include protofascist, totalitarian, extreme rightist and, most frequently, racist.

Le Pen himself has, of course, his own view. Sitting quietly in the backyard of his ancestral home in Brittany, where sky-blue hydrangea flourish against the bright whitewashed exterior of a centuries-old mariner's home, he comes across as something of an intellectual. Yet he speaks in blunt, colorful language very different from the refined parlor talk of most of the members of the French political class, who, he claims, are out of touch with the everyday reality of their country. Le Pen portrays himself as a misunderstood man, the victim of a ''witchhunt'' carried out by his enemies in the press.

''People who are frightened by me are those who have created their own phantom, like people who carve a monster's face out of a pumpkin, put a candle inside it, and are then scared by their own creation when they see it glowing outside of their houses,'' he said. ''They have created a Jean-Marie Le Pen that has nothing to do with the real Jean-Marie Le Pen.''

He cites an example, that of the journalist who claimed to be frightened not by what Le Pen says but by what he does not say, implying that his language is a coded incitement to racial hatred. ''You can use that technique against anybody,'' Le Pen said. ''There's a facile sort of dialectic by which people who disagree with me automatically make the connection with Auschwitz. I totally reject that method of reasoning. Nazism is at the very antipode of what we represent.'' (''Whenever the television is here,'' he told an appreciative audience in La Baule, on the Breton Coast, raising the specter of the accusatory press, ''the cameras are attracted immediately to the only shaved head in the hall, even if there are 10,000 other heads that are not shaved. And the suggestion is that behind that single shaved skull among my supporters are harbored I do not know what sorts of dictatorial machinations. And so, if the actual discourse of Le Pen appears too moderate, if it seems to be actually reasonable, then at least the television has a shaved skull to broadcast to show that Le Pen could not be these things.'') According to Le Pen, the National Front represents the true classic right in France, where, he says, the conservative parties from de Gaulle onward have carried out ''leftist policies'' even as they have held to a rightist vocabulary. He accuses the established parties of being rife with ''sclerotic privileges'' paid for by the taxpayers. ''Moliere's miser,'' he said, referring to the play, ''hoarded money, but it was his own money. The minister of finance hoards the money that the French have labored to produce.''