( dpa )- Spaniards were voting Sunday in parliamentary elections expected to become a close race between the governing Socialists and the opposition conservatives after a killing by the militant Basque separatist group ETA cast its shadow over the vote.
About 35 million people were eligible to elect 350 members of the lower house of parliament and 208 of the 264 members of the senate.
It was thought possible that the shooting of Socialist councillor Isaias Carrasco in the Basque town of Arrasate on Friday might increase voter turnout.
That could favour Prime Minister Jose Luis Rodriguez Zapatero's Socialists, whom polls gave a slight lead over the opposition conservative People's Party (PP) headed by Mariano Rajoy , but whose supporters have traditionally been less disciplined in going to the polls.
" Spain is stronger if all of us citizens go to vote," Zapatero said on casting his ballot.
Rajoy called on Spaniards to vote "thinking about themselves and the future of their country."
Voters included the widow of Carrasco, whose daughter had appealed to Spaniards to vote in solidarity of his family.
While a higher turnout could favour the Socialists, it was also deemed possible that Carrasco's killing could make more voters choose the PP because of its tougher line on ETA.
Former Socialist councillor Carrasco was gunned down as he was about to leave home by car. Police were searching for two ETA activists.
Carrasco's family had Saturday declined to personally receive Rajoy's condolences. Media close to the conservatives or Socialists accused politicians of the rival party of trying to make electoral use of the tragedy.
Nearly 90,000 police were ensuring security after the level of terrorism alert had been raised ahead of the electoral campaign.
Zapatero had pledged to seek an absolute majority to be able to govern without the support of smaller leftist and regionalist parties, as he has done until now.
Zapatero took a surprise victory after eight years of conservative rule in 2004 after Islamist extremists killed 191 people in the Madrid train bombings three days before the poll.
Many voters attributed the attack to the then conservative government's alliance with the United States in Iraq and suspected the government of lying when initially blaming the bombings on ETA.
The subsequent legislature was characterized by constant tension between the opposition and the government, with the PP strongly condemning Zapatero's failed attempt to negotiate with ETA.
The electoral campaign has also been unusually virulent, with Zapatero and Rajoy accusing each other of lying during two live television debates watched by more than 10 million people.
The Socialists' biggest weakness was thought to be the economy, which has slowed down after a decade-long boom.
Unemployment, which had dropped from 22 per cent in 1996 to around 8 per cent, has started going up again, partly because of a meltdown in the construction sector, and indebted consumers are struggling with rising food and fuel prices.
The PP has also accused the government of not controlling the entry of illegal immigrants, whose number the party has put at more than a million, while Zapatero and newspaper reports estimated it at up to 250,000.
In addition to disputes about anti-terrorism policy, Zapatero's term in office has been marked by sweeping social reforms which have contributed to transforming Spain from a conservative Catholic country to one of Europe's most liberal ones.
Reforms included major women's rights legislation, including electoral parity. The parties had nearly as many female as male candidates in Sunday's elections, 75 per cent more than in 2004.
The Zapatero government also gave homosexuals full marriage rights, including the right to adopt children. It adopted a comprehensive law against domestic violence, made divorce easier, and reduced the Catholic Church's influence on education.
The reforms put Zapatero on a collision course with the church, but the PP has refrained from attacking them head-on.