PARIS - French President Nicolas Sarkozy's center-right bloc suffered a comprehensive defeat in Sunday's local elections, but managed to cling on to power in one mainland region to avoid a whitewash, exit polls said. The Socialist party and its allies won some 54 percent of the vote at a national level, to give the left control of at least 20 of the 22 regions up for grabs on the mainland, while the center-right won 36 percent, OpinionWay pollsters said. The far-right National Front took just 8.7 percent nationwide, according to OpinionWay, but veteran party leader Jean-Marie Le Pen secured backing of almost 25 percent of voters in his region in the far south of France, it predicted. Although Sunday's result represents a triumph for the Socialists, the fact the center-right appeared set to hold on to the Alsace region in the east was a big relief for Sarkozy, who has come under criticism from his own camp over his policies. Pollsters said the feeble economy and growing unemployment had taken its toll on the government, with a string of recent controversies, ranging from accusations of nepotism to a debate on national identity, also eroding Sarkozy's popularity. He has already promised a pause in reform next year and a heavy loss in the last midterm election before 2012 could make him more cautious about pushing potentially painful cuts in the big projects which remain in 2010. The president is planning a major overhaul of the pensions system, including raising the retirement age, and he also needs to rein in France's public deficit, which is expected to reach 8.2 percent of gross domestic product in 2010. He could find both efforts more difficult if serious electoral losses undermine public support for change in the euro zone's second biggest economy. The powerful CGT union has already called for a day of protest over wages and pensions on Tuesday. Other groups, such as farmers, may also see a big defeat for the center-right as an opportunity to put pressure on the government. The 26 regional councils on the mainland and in far-flung overseas territories are responsible for issues such as school buildings and local transport. They have very little economic power and normally attract scant interest even inside France.