Madrid — For the third time since the first free elections in 1977, Spaniards will be flocking to the polls on Oct. 28 for national elections.
And for the first time since Spain's bitter civil war in 1936-39, the left is expected to win. All polls predict a sizable victory of 45 to 55 percent of the votes for the Spanish Socialist Workers' Party, led by charismatic Felipe Gonzalez, known here simply as ''Felipe.''
Spaniards have reason not to be nonchalant about voting. Unlike other Western industrialized countries, democracy still seems to be a fragile but cherished novelty, constantly threatened by the specter of a return to military dictatorship.
Since the 1977 elections, the ruling center government of Spain's fledgling democracy has survived no fewer than four major military coup plots to overthrow the government. Only two weeks ago, the last, and best-prepared, plot, carefully planned for the day before elections, was uncovered.
The transition to the first free elections in 1977, after the 1975 death of Generalissimo Francisco Franco and 40 years of dictatorship, was itself a unique nonviolent experiment. Under the guidance of King Juan Carlos, Spain was gradually transformed into a tentative democracy using the same political tools of the dictatorial regime. These tools were themselves only gradually replaced by modern democratic instruments and a new Constitution. However, the armed forces and the judicial system, the last bastions of Franco's Spain, still remain in need of some democratic remodeling.
Constantly under the shadow of another coup plan, many Spaniards see the Socialist Party as the only party strong and stable enough to stand up to the old guard military establishment.
''The armed forces,'' Felipe Gonzalez stated for television, ''like everyone else, wants a government that's capable of governing. I don't believe a Socialist administration would cause a new coup. Democracy is consolidated by the alternation of power.''
In reference to the last coup attempt planned for Oct. 27, Gonzalez affirmed at a rally, ''True investigation will happen after Oct. 28, because, first of all, we Socialists have democratic determination and we believe that only the state has the privilege of force.
''In the second place,'' Gonzalez added with a smile, ''we will get to the bottom of it out of an elemental instinct of self-preservation. . . . Democracy has a right to defend itself.''
The Socialist Party has stated continually that it will use a selective promotion policy in the armed forces and, if lacking sufficient evidence for convictions, will banish the unredeemable plotters to destinations where, at least, they can do no more scheming. The party plans to reform the military academy system where cadets are still taught to see the Socialists as ''Marxist hordes,'' and hopes to buy good will by raising salaries, bettering living conditions and military housing, modernizing and professionalizing the armed forces with new equipment and specialized training for high technology occupations.
Having charmed bankers, businessmen, and multinational executives in numerous public relations luncheons, Felipe Gonzalez admits, nevertheless, his party has had much less contact with the military. But like spokesmen from the business and banking community, official armed forces spokesmen have affirmed they will accept a democratically elected Socialist government.
Miguel Angel Aguilar, military affairs journalist for El Pais, Spain's largest and most prestigious daily, commented, ''The Socialists will gain the respect of not only the armed forces, but also of the entire nation if they can energetically move against the plotting elements of the Army. This will restore credibility and respectability to the armed forces whose image is so tarnished after these coup attempts.''
''The armed forces best understands a strong stable power that clearly explains things. For them a government that can't govern illustrates the failure of democracy,'' insisted Luis Solana, Socialist member of Parliament and spokesman on military issues.
Although the backdrop of another possible coup attempt differentiates Spain from modern Europe, Spanish voters, like other European voters, who have weathered endless economic recessions, seem ready to ''vote for change,'' the main slogan of the Socialist Party. After bitter party infighting and defections to the right and left, Spain's ruling Union of Democratic Center (UCD), that won both the 1977 and 1979 elections, has dwindled into two small center parties. Defectors to the left have joined ranks with Felipe Gonzalez and defectors to the right have sided up with Manuel Fraga, leader of the right-wing party, Alianza Popular (Popular Alliance).
With the virtual disintegration of the ruling center party, Spain has evolved into a practical, two-party system. If short of an absolute majority, the Socialists have reiterated they will form coalitions with the center parties, ''never, never,'' they say, with the Communist Party, which is also expected to lose heavily.
Like other democratic countries, the political platforms offered by the major parties seem almost identical. Joaquin Almunia, a Socialist spokesman explained that the differences are to be found in nuances and the ''determination to apply the program.'' The Socialists, according to Mr. Almunia, ''will combine a free market economy with compensatory social elements.''
Fraga, like other European conservatives, promises to reduce taxes and warns of horrendous public deficits under the Socialists. But he suffers a tarnished image from his ministerial post under the Franco regime.
''My natural inclination would be to vote Popular Alliance,'' said Antonio Garcia Ferreiro, an economist and small businessman who has 50 employees. ''But I just can't. I remember as a student when Fraga was my professor and came to class with a gun. He's still a totalitarian at heart; I don't trust (him).'' Mr. Garcia plans to abstain from voting.
There has been some concern in Washington over some of the aspects of the Socialist foreign policy. Felipe Gonzalez has said he will call for a referendum on NATO membership and possibly review the US-bilateral friendship agreement. But as with Greece, most political commentators here feel these statements are basically electoral and would be extremely difficult to implant.
More than any specific platform, the Socialists with their energetic leader have managed to give off an image of freshness, incorruptibility, and good humor.
''I don't know if the Socialists are going to be any more efficient,'' a Spanish journalist commented, ''but they're certainly going to be more fun.''