PARIS French far-right leader Marine Le Pen accused the two major parties on Sunday of telling mayors across the country not to endorse her presidential candidacy, a move her allies said was "muzzling democracy."
Despite strong public support, Le Pen says she is 150 signatures short of the 500 required from elected local officials in order to stand.
Speaking at a campaign rally in the southwestern city of Toulouse, she urged mayors to ignore the "lies" of the frontrunning Socialists and the conservative ruling UMP party.
"Those cliques are giving lessons on democracy when they are the ones that are lying," she told supporters. "It's not me that the system wants to shut up, it's the French people."
Le Pen is running third in opinion polls, with 15 to 20 percent of voter intentions ahead of the April 22 first round. Like her father Jean-Marie in 2002, she hopes to knock out one of the frontrunners to reach the two candidate run-off on May 6.
At one point in January she was a couple of points behind incumbent Nicolas Sarkozy but has since slipped back.
According to a newspaper poll published on Sunday, Sarkozy would benefit most if the former lawyer was unable to stand.
The survey for Journal du Dimanche showed the president would pick up 8.5 points, while his Socialist challenger Francois Hollande would win 3.5 points more, leaving them level on 33 percent after the first round.
Defence Minister Gerard Longuet, a member of Sarkozy's party, said on Sunday it would be a backward step if Le Pen failed to make it through.
"She represents a political trend and this movement should be able to express its views," he said.
"But we have to ask ourselves why not even 1 percent of (about 36,000) mayors are not signing up for her. Maybe it's because she says some absurd things."
National Front Vice-President Louis Alliot suggested "establishment" parties were indirectly encouraging elected officials, of which the bulk are from the two main parties, not to give her the backing she needed.
"(There are) political calculations aimed at muzzling democracy and preventing all opposition to the establishment," he said in a statement on Sunday.
Prime Minister Francois Fillon and Socialist Party chief Martine Aubry have both said Le Pen is bluffing. The suggestion she may not get sufficient official backing is seen as a ploy to promote her outsider status and remain in the public eye.
"For weeks I've been trying to get nominations, but they have been preventing me," Le Pen told jubilant supporters.
Prospective candidates have until March 16 to secure enough signatures and Le Pen has taken her case to France's highest court to challenge the 1976 rule, arguing many officials would rather choose anonymously and are boycotting the process.
The Constitutional Council is set make its decision before February 22.
Le Pen, who replaced her father as party chief last year, has tried to broaden the National Front's appeal beyond its traditional anti-immigrant base to a younger generation with a more anti-euro and protectionist stance.
She says a failure to secure 500 endorsements, like her father in 1981, would represent the end of French democracy, given that a fifth of voters would be effectively denied a vote.
(Reporting By John Irish; Editing by Sophie Hares)