A special new effort is being made to mobilise French Muslims to speak up at the ballot box in Sunday's presidential race - amid a surge of Islam-bashing among the French right.

Imams and Islamic associations are calling on Muslims to do their duty as citizens and go to the polls.

And while they are not officially endorsing anyone, the call itself is a bold move in a country where statistics on religious affiliation are formally banned and where secularism is enshrined in the constitution.

Socialist Francois Hollande - the poll favourite - is more likely to benefit from the get-out-the-vote push, because conservative President Nicolas Sarkozy has spoken out against Muslim practices in his campaign and experts say that Muslims in poor neighbourhoods and Muslim youth tend to vote for the left.

But the Muslim vote is diverse, and there is no guarantee that the push will bring out voters, since Muslims have tended in the past to avoid politics.

French Muslims have been pounded with blame throughout the campaign for what they eat (halal meat), how they pray (in the street), and for allegedly using their growing numbers to supplant France's civilisation with their own.

The massacre of Jewish schoolchildren and French paratroopers in March by an alleged Islamic extremist put Muslims in the spotlight anew and fed far-right fear mongering.

Under the banner of patriotism and preserving the national identity, Mr Sarkozy is trawling for far-right votes as he tries to undo Mr Hollande.

Far-right candidate Marine Le Pen, who ran an anti-immigration and anti-Europe campaign and sowed fears that France is being Islamicised, placed a strong third in the April 22 first-round vote.

Though she was eliminated, her 18% score was a historic high for her National Front party and her supporters could now boost Mr Sarkozy's support in the runoff.

For some Muslim religious leaders, it is time to act.

"We don't live on Mars. We live in France and we are constantly listening to what is happening," said Kamel Kabtane, the rector of the Lyon mosque, who was among a group of imams at some 30 mosques in south east France pressing Muslims to vote.

"By this initiative, we want to show that Muslims aren't citizens of the second zone ... They can vote for whom they want but be present in the voting booth," he said.

The more than five million Muslims in France - the largest such population in western Europe - could potentially prove a decisive weight for or against a candidate.

But experts say their footprint on the political landscape is nearly invisible.

The French model of integration is officially colourblind, demanding that immigrant minorities forgo their customs to meld into the universe of Frenchness.

Statistics on race, ethnic origin and religion are formally banned, though researchers find ways to circumvent the rule, like using last names to deduce who is who.

Mr Kabtane said the Muslim get-out-the-vote initiative in south east France was the first of its kind, although some mosques in the Paris area are also asking Muslims to go to the polls.

In most cases, imams say they make a point not to advise the faithful how to vote.

However, an expert on secularism, Jean Bauberot, says the anti-Muslim rhetoric by the right makes the preferred candidate clear - the one on the left.

"In the current atmosphere, Nicolas Sarkozy is doing all he can to alienate the Muslim electorate ...," Mr Bauberot said. "When they (imams) say go out and vote, people think ... you shouldn't vote for Sarkozy."

For the head of the Grand Mosque of Paris, Dalil Boubakeur, such calls to vote are dangerous because they risk dragging a religion into politics, and: "I refuse it."

The Paris mosque issued a statement saying it opposed the Lyon call.

"Mobilise, yes, but not in the name of Islam," he said. "In the name of justice, the economy, housing projects, misery, unemployment. But not in the name of Islam."

However, other Paris imams have pressed for Muslims to vote, including Mohamed Saleh Hamza who heads the northern Paris mosque where, until last autumn, the faithful spilled into the street to pray because crowds had grown too big to fit inside.

For Ms Le Pen, the street prayers were ammunition for her anti-Islam cause.

Mr Sarkozy took up the call and a giant prayer room was opened in a firehouse barracks where thousands now pray.

At Friday's prayer service in the new space, there was no mention of the presidential election; the sermon was on the power of love.

Earlier, however, mosque leader Mr Hamza had called for Muslims to go to the polls.

Muslims "have a tendency not to vote. Now, we're telling them that they are full citizens", Mr Hamza said. "They're not organised yet, but that will come."

The calculations of the Mosque of Paris puts the number of Muslim voters at some 10%. It's a diverse population, most with family origins in former colonies in North Africa and Saharan Africa, and political opinions are not homogenous.

Experts say that Muslims in poor neighbourhoods and Muslim youth tend to vote for the left.

Mr Sarkozy has walked both sides of the line in addressing Muslims.

While campaigning, he has spoken out against Muslim prayers in the street, the multiplication of halal butchers and the immigrant flux, in France seen as mainly Muslim.

However, he embraced the Muslim population at the start of his term in 2007, appointing two ministers of Muslim North African origin and working for an Islam of France.