Spain's governing Socialists suffered a crushing defeat in nationwide municipal and local elections held Sunday.

The Socialist Party, or PSOE, lost one of its traditional strongholds, the central autonomous community of Castilla-La Mancha, and could lose Extremadura once all the votes are tallied.

The center-right opposition Popular Party, or PP, won the municipal elections nationwide by a margin of 10 percentages points and secured a clear victory in the regional elections as well in a vote that had been widely touted as a bellwether for the general elections in March 2012.

In Castilla-La Mancha, which had been governed by the Socialists since the beginning of Spain's democracy after the Franco dictatorship, the PP obtained an absolute majority and will take over the region's governmental reins.

The leader of the Socialists in the region, Jose Maria Barreda, acknowledged the PP's triumph, calling it a "resounding" win, with the conservatives attaining an absolute majority of 27 seats in the regional legislature, compared to 22 for the PSOE.

In Extremadura, another traditional Socialist bastion, the PP was looking like the winner Sunday evening with just under 80 percent of the ballots counted, but the PSOE could still strike a deal with other political forces to retain its hold on power.

In addition, in municipal elections in Andalusia, another traditional PSOE stronghold, the conservatives prevailed by more than 7 percentage points over their socialist rivals.

With 97.33 percent of the vote in Andalusia counted, the PP obtained 39.51 percent while the PSOE garnered 32.16 percent, and those results will allow the PP to govern with an absolute majority in the region's eight major cities, given that the Socialists lost control of the city halls in Seville and Jaen, where they had been governing in coalition with the United Left party.

The Socialists also lost another of their longstanding strongholds - the city government in Barcelona - which will now pass into the hands of the moderate nationalists of the CiU.

Spain's Socialist prime minister, Jose Luis Rodriguez Zapatero, said that he will not move up the general elections scheduled for next March, and he acknowledged that his party had suffered "a very broad setback" in the local voting across the country.

He said that the results of the election have "a very clear relationship with the effects of the economic crisis" that has beset the country for three years, adding that "we accept and understand the punishment at the polls."

Zapatero said that his party will decide the schedule for the internal process to elect a new PSOE candidate for prime minister in the 2012 vote, having announced on April 2 that he would not seek a third term.

Voters went to the polls to elect mayors and councilors for four-year terms in more than 8,100 municipalities, as well as the members of the legislatures of 13 of the country's 17 regional governments, with Andalusia, Catalonia, Galicia and the Basque Country being the only exceptions.

The elections took place amid protests that began on May 15 at Madrid's Puerta del Sol square and in other Spanish cities.

The thousands of young people and supporters of the May 15th Movement have been demanding democratic renewal and changes in efforts to deal with Spain's deep recession, which has produced an unemployment rate of over 40 percent among those 25 and younger.

Demonstrators reject the current austerity policies and express disgust with both the Socialists and the PP.

Protesters gathered at the Puerta del Sol agreed on Sunday to keep up their protest for at least another week, until next Sunday, to better express the desires of the movement's members and to have the best chance possible to achieve social change in Spain.