A wave of nationwide protests against soaring unemployment and the economic crisis is overshadowing local elections in Spain in which the ruling Socialist Party faces the prospect of a humiliating defeat.
The predicted rout would be a bad omen for the party ahead of general elections scheduled for March 2012, when the conservative Popular Party is expected to romp back into office after eight years in opposition.
More than 34 million people are eligible to vote on Sunday, choosing thousands of mayors, town councillors and members of regional parliaments.
Polls forecast devastating losses for the Socialists as voters take revenge for the destruction of millions of jobs and painful spending cuts, including to state salaries.
They predict the ruling party of Prime Minister Jose Luis Rodriguez Zapatero will lose control of strongholds such as the cities of Barcelona, Seville and in the central region of Castilla-La Mancha.
The campaigning and the predicted outcome have been largely obscured - and muddied by - a nationwide protest movement that began 15 May by youths angry over joblessness, the economic crisis, politicians in general, and corruption.
The crisis pushed Spain's unemployment rate to 21.19% in the first quarter of this year, the highest in the industrialised world.
For under-25s, the rate in February was 44.6%, and some 800,000 young people are eligible to vote for the first time on Sunday.
The government has resisted ordering police to disperse the demonstrators, apparently fearing it could hurt the Socialists at the polls.
Thousands of demonstrators, mostly young people, late Saturday filled Madrid's Puerta del Sol square, where a ramshackle protest 'village' has sprung up, in a gathering that lasted into the early hours of Sunday.
Demonstrations were also held in some other cities, including Valencia and Barcelona.
Much of the focus on Sunday was also on the northern semi-autonomous Basque Country, where a new political force, Bildu, is taking on the traditional parties after a court battle to prove it is not a mouthpiece for armed separatist group ETA.