AMIENS, France (Reuters) - On a school gate in the French city of Amiens, a hand-written note details the results of last weekend’s parliamentary elections. The winner, by far, was abstention.

Barely a third of the 1,803 registered voters in the working class neighborhood of Saint-Maurice bothered to cast a ballot at the school, which doubles up as a polling station.

The dismal turnout in the first round of the elections could spell trouble for President Emmanuel Macron, who was born and grew up in the northern city. While his party is forecast to win the second round run-off this Sunday easily, he will need all the support he can get to avoid street protests that could hinder his plans for far-reaching social and economic reforms.

Local people who stayed at home last weekend spoke of their disillusionment with politics in a country where job creation has been slow and frustration with an election where the result already appears a done deal.

“We’re in deep shit already and we’ll never get out of it, at least not for a long while, so what’s the point in going to vote?” Amelie Leroy, a 25-year-old maternity ward worker, told Reuters on a quiet street of yellow and red brick houses.

These are emotions felt across France, a country where voter turnout is traditionally high but slumped to just 48.7 percent in the first round, the lowest for a parliamentary election in the country’s modern history.

Opinion polls project that the run-off - contested by the top two candidates from the first round in each constituency - will hand Macron’s centrist Republic on the Move (LREM) party and its smaller ally as many as three quarters of the 577 seats in the lower house.

That on paper would give Macron a powerful mandate for his reform plans that include cutting tens of thousands of public sector jobs and making it easier to hire and fire workers. But his party and its ally won just about a third of the low first round vote.

An OpinionWay poll on Thursday pointed to an even lower turnout of 46 percent in the run-off.

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This high abstention rate shows Macron, a 39-year-old former banker, is struggling to rally the whole nation behind him. That means he will have to tread carefully in a country where muscular trade unions do not shy from calling strikes and where street protests have forced many a past government to dilute reforms.

Leroy, who will stay at home again for the run-off, said she knew little about the candidates courting her vote, but did know about Macron’s plans to relax labor laws. And they worry her.

If he goes through with them, Leroy said, she would probably take to the streets in protest, or strike.

A survey by Elabe pollsters showed not all of those who abstained last Sunday did so in protest - 47 percent welcomed the outcome. But even the government has said the low turnout was a failure it needed to address.

“That’s what’s at stake in this second round vote but also for our whole five-year term - reconciling the French with politics and bringing voters back to the ballot box,” said Nicolas Dumont, the 40-year-old candidate for Macron’s party in the Amiens constituency where Leroy lives.

Dumont got just 210 votes cast at the Saint-Maurice school, exactly the same as Francois Ruffin, a hard-left activist who he will face in the June 18 run-off.

Many local people are unconvinced by Macron, who became modern France’s youngest president last month.

“We elected a 39-year-old, a former Rothschild banker. How do you want this guy to put himself in the shoes of the average worker? That will never happen,” said 63-year-old retired factory worker Philippe Lamour, a far-right sympathizer.

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Lamour, who usually votes, is boycotting what he calls a “moronic” parliamentary election this time because he feels a LREM victory is a foregone conclusion.

After months of political campaigning marked by scandals, even Macron supporters are wary.

Sitting in the sun on the steps of her home, 72-year-old Amiens resident Francoise Granger said she is backing both Macron and Dumont. However, she is also worried by allegations of impropriety concerning two ministers in his government. “There needs to be full transparency,” she said.

NO BLANK CHECK

The large parliamentary majority that is expected for LREM should not be interpreted as a blank check for Macron, said Yves-Marie Cann of Elabe.

“It will not exempt the government from having to seek a wide majority for its projects, or else it would run the risk of angering part of the population and foster protests that could benefit from substantial support among the population.”

Macron has said labor reform is one of his top priorities and has planned to ask the new assembly, which starts work on June 27, to let him to speed up its adoption via executive decrees rather than parliamentary votes. But, in an attempt to win backing for the reform, he has also planned a series of meetings with labor unions to discuss his plans.

At this stage, the momentum behind Macron is such that active opposition to him is weak, Cann said. One in two of those voters who backed his main anti-establishment rivals for the presidency - hard-left candidate Jean-Luc Melenchon and far-right contender Marine Le Pen - didn’t vote in the parliamentary election’s first round.

Generally, the lower a citizen’s salary and educational levels, the higher the likelihood of abstention, an Ipsos Sopra Steria poll showed. Age also plays a role.

“We know that it’s the workers who won’t go and vote, we know it’s young people who won’t go and vote,” said Ruffin, who came well behind LREM’s Dumont in the Amiens constituency in the first round, with 24.32 percent versus 34.13 percent.

But in a city with a history of headline-grabbing industrial action, trade unionists said the apathy would not last.

“It’s not done yet. I hope he (Macron) is expecting tough protests when he puts his reform on the table,” said Frederic Chantrelle, a member of the CFDT union who has worked for 20 years at a local tumble-drier factory.

(Corrects projected turnout to 46 percent in paragraph 9.)