From Far Right, Squeezing Into the Middle PARIS - With just 100 days to go before presidential elections, the populist, anti-euro message of Marine Le Pen, the leader of the National Front, appears to be gaining resonance here. That message coincides with a mounting anxiety over the costs to France of Europe's scramble to rescue the single currency amid an ever-darkening outlook for economic growth. In opinion polls published this week, Ms. Le Pen, the expected candidate of the far right, trailed President Nicolas Sarkozy by only the slimmest of margins, a development that the candidate on Friday hailed as evidence of a growing distrust among the French of mainstream politicians. "We see potential for progress that is not negligible," said Ms. Le Pen, noting that the result was "historically high" for the party founded by her father, Jean-Marie Le Pen, who famously made it to the final runoff against Jacques Chirac in 2002 by capturing a mere 17.5 percent of the first-round vote. A poll conducted Jan. 9-12 by Ifop-Fiducial and published Friday in the magazine Paris Match, showed that François Hollande, the Socialist candidate, remained in the lead, with 27 percent of the 943 eligible voters polled indicating they would choose him if the first round of voting, scheduled for April 22, were held today. Support for Mr. Sarkozy, meanwhile, stood at 23.5 percent, just ahead of Ms. Le Pen, with 21.5 percent. In a second poll of 875 eligible voters conducted by the CSA agency on Jan. 9-10, Mr. Sarkozy maintained a larger margin, with 26 percent saying they would vote for the president, against 19 percent for Ms. Le Pen. Mr. Hollande would secure 29 percent. Neither polling agency provided a margin of sampling error. Ms. Le Pen, 43, is the youngest of Jean-Marie Le Pen's three daughters. But the twice-divorced single mother of three continues to face an uphill battle to enter the final round, scheduled for May 6, with the latest polls consistently indicating that Mr. Hollande, 57, would defeat Mr. Sarkozy, 57 percent to 43 percent. But the growing popularity of her platform - which advocates a return to the French franc, tighter restrictions against immigration and state intervention to protect French industries from foreign competition - appeared Friday to have emboldened her, as she hinted at a silent constituency that had yet to make itself heard in opinion surveys. "We do not yet know the level of "under-declaration" of support" for the National Front, she said. Indeed, a third poll published Friday in Le Monde indicated that 31 percent of the French were "in agreement with the ideas of the National Front," up from 22 percent a year ago and 11 percent in 1999. While the survey of 1,000 people age 18 and over conducted by TNS Sofres showed that only 11 percent supported the party's specific proposals, it affirmed that the far right was deepening its appeal among the working class and in rural communities, which have thus far borne the brunt of France's economic slowdown. "We are witnessing a de-demonization of the National Front," said Emmanuel Rivière, the director of opinion strategy at TNS Sofres. In a sign of her mounting confidence, Ms. Le Pen challenged Mr. Sarkozy to abolish current election rules that require the public disclosure of the signatures that presidential candidates must obtain from at least 500 mayors before they can appear on the national ballot - a bar that Ms. Le Pen and other center-right candidates, including Mr. Sarkozy's rival Dominique de Villepin, have yet to meet. The lack of anonymity, she said, was "undemocratic" and she warned that the requirement could ultimately backfire on the president. "If I am not on the ballot, Nicolas Sarkozy will lose," Ms. Le Pen said. "The voters of the National Front will take their revenge" at the ballot box. Mr. Sarkozy, who turns 57 later this month, has yet to formally declare his candidacy. His popularity has languished at all-time lows for months, opening the door to challengers like Ms. Le Pen, Mr. Villepin and François Bayrou, a centrist who finished third in the 2007 presidential race. Assuming Ms. Le Pen does secure a place on the ballot, analysts said they could not rule out the possibility of her making it through to the final runoff. "The game is extremely open," said Damien Philippot, a research manager at the Ifop polling agency. The big difference between this and past elections is that if Marine Le Pen does make it into the second round, it won't be a big surprise.