Campaign volunteers for the leader of the political movement "La France Insoumise" Jean-Luc Melenchon are gearing up for what they expect will be a massive march in Paris for the far-left candidate.

The "March for the Sixth Republic" planned on Saturday (March 17) aims at gathering citizens around Melenchon's project for a new constitution and new institutions.

An IFOP daily poll of voting intentions on Thursday (March 16) showed Melenchon trailing in fifth place, getting 11 percent of the vote in the first round.

His campaign march five years ago, dubbed as the "Storming of the Bastille" gathered tens of thousands of people. This year, Melenchon plans to deliver a speech at the Place de la Republique.

A coordinator for the volunteers' group of Melenchon's movement, Romain Jammes, says he supports the idea of a sixth Republic because of the ever-widening gap between politicians and citizens. He pointed out the formal charges against conservative candidate Francois Fillon for alleged misuse of public funds.

"The sixth Republic, it echoes this feeling that we are being ripped off in this story," Jammes said.

The French far-left candidate is a well-known firebrand figure of the national political scene.

In the 2012 presidential election, Melenchon pulled a surprise when he emerged as fourth place after the first round, with more than 11 percent of the vote.

Since then, he has reshaped his political programme to incorporate environmental themes.

He has also used YouTube to reach a younger generation of voters.

Member of the European parliament since 2009, he had opposed the passage of the free-trade agreement between Canada and the European Union and has lobbied for greater regulations within the European Union.

In 2015, he supported the "no" vote in the Greek referendum on bailout terms, as an ally of Greek Prime Minister Alexis Tsipras.