France's centre-right UMP party and its allies made strident gains in local elections on Sunday, delivering a winding blow to President François Hollande's Socialist party.
The UMP, led by the former president Nicolas Sarkozy and in an election coalition with the centrist UDI party, won between 66 and 70 départements compared with 41 previously, according to projections from polling companies.
By contrast, the Socialist party looked to have held on to between only 27 and 31 — barely half the 61 départements it controlled before.
The far-right National Front (FN), meanwhile, appeared to have made considerable ground in Sunday's second-round vote — though it was unclear if it had done enough to win full control of any départements.
Even so, the anti-immigration, anti-euro party led by Marine Le Pen is likely to have done much to boost its national presence as it looks ahead to the 2017 presidential election. The FN has made important gains in recent years, wooing voters from both left and right, disillusioned by the lack of economic growth and high unemployment.
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Following on the back of last year's success in European elections over France's two mainstream parties, Ms Le Pen called Sunday's result "the foundation of tomorrow's big victories".
Yet the undoubted winner of the night was Mr Sarkozy, whose return to national politics late last year had so far failed to provide the spark that he had promised — and for whom victory in Sunday's second-round vote was considered essential.
Celebrating what appeared to be a thumping victory over Mr Hollande's Socialists, the former president said triumphantly: "The French have voted massively to reject the policy of Hollande and his government."
The results, if confirmed, amount to a clear defeat for Mr Hollande, just as his government was trying to push through economic reforms this year to capture early signs of recovery in Europe's second-largest economy.
Speaking on Sunday, Manuel Valls, the prime minister, acknowledged defeat. "It is incontestable," he said, blaming divisions in the left that he said had proved deadly.
Earlier this year, Mr Valls was forced to push one of the government's key economic reforms through parliament by decree as he headed off a possible revolt by far-left members of his Socialist party.
Mr Valls said Sunday's defeat would nonetheless do nothing to sway the government from its reformist path.
Jubilant, Mr Sarkozy said: "Announcing that the vote today would do nothing to change its policies, Hollande has deliberately chosen to ignore the message delivered by the French."
With Sunday's local election safely behind him, Mr Sarkozy will doubtless already be looking ahead to next year's UMP primary elections to choose a presidential candidate.
The former president, whom Mr Hollande beat in 2012, has yet to declare his intentions to return to the Elysée, although most political analysts take it as a given.