A victory for opposition leader Mariano Rajoy of the conservative People's Party appears to be a foregone conclusion and the main question is exactly what austerity measures he plans to impose to steer Spain away from economic meltdown.
A gloomy mood hung over the country on Saturday, with little apparent excitement for the election.
High unemployment, cuts in public spending, and fears that Spain could become the next euro zone country to need a rescue package for its debt problems have sapped morale and dominated the election campaigns.
Lines of people formed in central Madrid on Saturday morning -- not in anticipation of polling stations opening, but to buy tickets for the national Christmas lottery, known as El Gordo, which could make them instant millionaires.
"We're going to buy lottery tickets to see if we win, that's
the only way things will change," said Ana Maria Gomez, 42-year-old housewife. "Everyone is very pessimistic, there's no work there's no hope."
Also standing in line at the Puerta del Sol, Madrid's main gathering ground, was Amparo Garcia, an 82-year-old retiree.
"I hope things improve because I have two grandchildren without work - one of them a father of triplets. Jobs are essential, especially for parents of families," she said.
Other elderly folk complained that their pensions had been frozen by the ruling Socialist government.
Opinion polls give the People's Party an unassailable lead over the Socialists, widely seen by Spaniards as having mishandled the response to the growing euro zone debt crisis.
Such is the unpopularity of Prime Minister Jose Luis Rodriguez Zapatero that he decided not to stand for office again.
His chosen successor, Alfredo Perez Rubalcaba, has virtually given up in the past few weeks and his campaign has focused on warning of the dangers of an over-powerful rightist government.
Ana Maria Lopez, a 53-year-old chiropodist, poured scorn on the Socialists and said she intended to vote on Sunday.
"This government is the worst, everything it touches it destroys. I want a change, I'm fed up with this," she said.
"I'm self-employed, this government has never given anything to the self-employed they only want our money and our taxes."
Several hundred demonstrators from Los Indignados (The Indignant Ones) movement gathered in the Puerta del Sol at midnight on Friday, waving their arms in the air in a silent protest and holding candles.
However, the turn-out was far less than their rallies earlier this year, when tens of thousands of people occupied town squares across Spain to protest against austerity measures and the political elite.
The movement has urged Spaniards to boycott both the People's Party and the Socialists at the ballot box on Sunday.
In his final rally on Friday evening, Rajoy told Spaniards bluntly that the road ahead would be difficult.
"We are not fooling ourselves, we're not going to sort everything out from one day to the other," he told thousands of blue-flag waving supporters in traditionally PP-supporting Madrid.
"We Spaniards know that it will take a lot of effort to get things done, and there is more effort ahead to take Spain forward. We know that nothing is free."
Rajoy must not only lead Spaniards out of their plight but also appease financial markets, who see the euro zone's fourth-largest economy as in danger of following Ireland, Portugal and Greece in having to seek an international rescue package.
The government sold bonds on Thursday with a yield of almost 7 percent -- a level of borrowing cost that led to the bail-outs in other euro zone countries.
In a glimmer of good news, the Spanish stock market closed higher on the last day of trade before the election. Investors saw Rajoy as winning the race with an absolute majority, giving him a strong mandate to carry out his plans.