The conservative Popular Party, led by 56-year-old Mariano Rajoy, would emerge with an unprecedented majority in the November 20 ballot, able to ram through reforms almost at will, the surveys said.
The Socialists' standard bearer, 60-year-old Alfredo Perez Rubalcaba, was leading his party to its greatest defeat since Spain returned to democracy after the 1975 death of General Francisco Franco, they said.

A total 45.4 percent of voters backed the Popular Party compared to just 30.9 percent for the Socialists, said a survey of 9,675 people by Metroscopia for centre-left daily El Pais. That would the give the Popular Party 192-196 lawmakers, an absolute majority of the 350-seat Congress of Deputies, the powerful lower chamber of parliament.

A poll by Sigma for rival centre-right daily El Mundo was even grimmer for the government, giving 47.6 percent support to the Popular Party and 29.8 percent to the Socialists. Such a result would deliver 198 seats to the Popular Party.

If the surveys are proved right on election day, the Popular Party would smash its previous record win in 2000 when Jose Maria Aznar took 44.52 percent of the electorate. Adding to the humiliation, the surveys showed the right winning in the southern region Andalusia, a Socialist bastion for 30 years but among the hardest hit by the crisis.

Spain's economy stalled in the third quarter with zero growth and unemployment soared to 21.52 percent in the same period, the highest in the industrialized world.

Spain's Socialists have been in power since 2004 under Prime Minister Jose Luis Rodriguez Zapatero, who has decided not to run again, and they now enjoy 169 seats in the lower house compared to 154 for the Popular Party.

Catalan nationalist party Covergence and Union would remain the third force in the parliament after the election, surveys showed, likely increasing their presence from 10 seats to 14. United Left, a coalition of left-wing socialists and greens, would snatch seven seats compared to just two now, the polls showed.

The party is widely believed to have benefited from the "indignant" protest movement, which says ordinary people are suffering from a crisis caused by big corporations, bankers and corrupt politicians.