Francois Fillon, member of Les Republicains political party and 2017 presidential candidate of the French centre-right, attends a political rally in Nice, France, January 11, 2017. REUTERS/Jean-Pierre Amet

PARIS (Reuters) - French conservative presidential candidate Francois Fillon tried to win over party critics at a meeting on Saturday at a time when polls show him losing some momentum due to what some say is too radical an economic reform program.

Surveys suggest Fillon will win the April/May election by a comfortable margin, but recent polls have shown his share of the vote in the first round falling.

Some senior members of his Republicans party, most often allies of former president Nicolas Sarkozy, have accused him of being too tough and have asked him to soften his program to avoid scaring off low-income voters.

“You will be the spearhead of my campaign, I will need each and every one of you,” Fillon told 2,500 party members, according to organizers. “I am calling for unity and total commitment to victory.”

Fillon’s program includes cutting business taxes, relaxing labor laws and scrapping the 35-hour working week in an attempt to boost growth, while also cutting half a million public sector jobs as part of a drive to shrink the state sector.

“This project -- I will explain it, I will clarify it, enrich it with your best ideas,” he told the first party conference since his victory in the primaries. But he said there would be no major changes.

Fillon’s average share of the vote in the first round has fallen in the latest opinion polls to 24-25 percent, depending on who runs for the Socialists, from as much as 27.5 percent a month ago.

The surveys show him trailing National Front (FN) leader Le Pen in the first-round vote on April 23, but indicate that he will pick up enough votes from other defeated candidates, including from some Socialists, to defeat her comfortably in the May 7 runoff.

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