Marine Le Pen’s far-Right National Rally party took the lead in the key battleground region of Provence in the first round of voting, the first exit poll said on Sunday night, amid a historically low turnout.

The regional election on Sunday was regarded as a major test of whether Ms Le Pen can win votes, less than a year ahead of a presidential election which is largely expected to pit the far-right leader against incumbent president Emmanuel Macron.

Overall, the National Rally party, or RN, is projected to have won 20 per cent of votes, a lower score than expected. Two exit polls showed far-right candidate Thierry Mariani winning in the southern region of Provence in the first round by a slim, and much smaller-than-expected, margin.

"We chose from the first round a strategy of rallying, in a region where the RN makes its highest scores in the country. The polls told us that we were more than ten points behind, I never believed it, because I know what I saw, I know what we went through, during the crisis that we went through," said Renaud Muselier, the conservative incumbent in Provence.

The number two of the far-Right party blamed the disappointing results on low turnout.

Turnout was at a historic low for a regional election, with only 33 per cent of voters having cast a ballot. In 2015, 50 per cent of voters had cast their ballots in the regional poll.

The conservative party obtained 27 per cent of votes, ahead of the Socialists with 18 per cent and the Green Party with 12 per cent. 

Mr Macron’s centre-right LREM party, however, only gathered 11 per cent of the vote and is not expected to win any regions.

Ms Le Pen has backed Mr Mariani, a former conservative minister who defected to her party, to run Provence-Alpes-Côte d’Azur – the vast French region encompassing the southern Alps, Saint-Tropez and Cannes on the Riviera, and the restive banlieues of Marseille to the West.

The RN already runs around ten towns in France, but it has never won one of the country’s 13 regions, which command a huge budget for managing schools, transport, culture and tourism. These are up for grabs this and next Sunday, along with assemblies for 96 departments, or counties.

One poll had suggested that Mr Mariani would come first in round one with around 42 per cent of the vote and could clinch the decisive second round in a week’s time whether or not his rivals gang up to keep him out – although the result could go to the wire.

Only candidates who gathered at least 10 per cent of the vote will go to the second and final round on June 27.

In the coming days, parties will be scrambling to form tactical alliances to keep the far-right party out – a longtime French tradition known as a "republican front."

The National Rally has increased its share of political victories in local elections in recent years, and has made security a top issue in the most recent campaign.

Its candidates have rallied around police unions who say they’re facing growing violence, and have called for tougher prison sentences and a moratorium on immigration, even though these fall within the powers of the national government and not the regional councils.

Mr Macron’s party is just four years old and so it did not exist the last time voters chose regional leaders in 2015.  It is facing disillusionment with Macron’s policies, including from rural voters who supported the yellow vest uprising against perceived economic injustice.

Ms Le Pen last night blamed the disappointing overall performance of her party on the low turnout. "How to explain the disenchantment of the French for this local election? As a republican, I can only regret this civic disaster…which gives a misleading vision of electoral reality," she said.

"The distortion between voting intentions in polls and reality has only one explanation: our voters did not come to vote," she added.

In the coming days, parties will be scrambling to form tactical alliances to keep the far-right party out – a longstanding French tradition which sees the Left pull out to help the mainstream Right win.