The far-right National Front strengthened its presence in France's grassroots politics on Sunday in a second round of local elections that TV exit polls showed was won by ex-president Nicolas Sarkozy's conservatives.
Sarkozy's UMP and its allies will take over 66-70 departements, up from 41, while the ruling Socialists will hold only 27-31 of the 61 they previously held, the poll by CSA for BFMTV said. A poll by Ipsos-Sopra Steria had similar results.
Marine Le Pen's anti-immigrant, anti-euro FN party was unlikely to win more than two departements, according to the polls, but will have a base of locally-elected officials to become more mainstream and better placed to contest national ballots. The FN previously controlled no departements.
Le Pen called the result “the foundations for the big victories of tomorrow”.
The FN came second last week in the first round of the local elections, winning one in four votes, and is all but certain to see a big jump in its total number of councillors, from only two.
Sarkozy said: “The French people have massively rejected the policies of Francois Hollande and his government.”
French Prime Minister Manuel Valls, whose deeply unpopular administration is trying to play up modest signs of recovery in the euro zone's second largest economy, spoke within minutes of the polls closing.
“The far right's strong, much too strong, results are a challenge to all democrats,” he said.
“This is a sign of a lasting upheaval of our political landscape and we will all need to draw lessons from it.”
He said would introduce new measures aimed at boosting employment.
The second round is a key test for Sarkozy, who put a shaky political comeback back on track by steering his conservative UMP party and its allies to an unexpected victory in the first round but still faces resistance within his party.
The FN, which topped last year's European Parliament elections in France, had eight of its candidates elected in the first round of the local polls and could see as many as 220 more elected on Sunday, still far fewer than the mainstream parties.
The complex election system, in which a duo of councillors is elected per constituency who then elect the presidents of 98 councils, means it may take time to form a clear picture of how many councils each party has won.
In total, 4,108 councillors with limited powers over roads, schools and social services will be elected. At 1700 (1500 GMT), voter turnout stood at 41.94 percent, nearly six points higher than in the previous local elections in 2011.