Managua, Nicaragua — With the withdrawal of the major Nicaraguan opposition leaders, most non-Sandinista politicians are calling this Sunday's election here a nonevent. But few watching the multilingual mobs of foreign journalists and electoral observers jostling for space around the Hotel Intercontinental's lunchtime buffet table would ever think to call it that.
Event or nonevent, this election in a small Central American country has attracted a great deal of international attention. More than 600 journalists and 400 electoral observers from international human rights groups and foreign governments have come to watch the first public referendum on the five-year-old revolutionary government.
Many of these observers, who are trying to assess the fairness of the electoral process, do not find their task an easy one.
Nicaragua's electoral picture cannot be reduced to simple black-and-white terms, they say. During August and September - the initial phase of the electoral campaign - press censorship was strong, although slightly improved over the Sandinistas' first years in power, these observers say.
In October the situation improved greatly, say both Western (non-US) diplomatic observers and Nicaraguan opposition leaders. Attacks by Sandinista mobs and harassment of campaign workers were largely stopped. Press censorship diminished to about half of what it was in September.
But some leading Nicaraguan opposition leaders say that one month of relatively free campaigning is simply not enough for a fair election.
This past week, the Sandinistas have made a last-minute push to get opposition parties to participate - against their will, if necessary.
The major opposition figure who remained in the campaign the longest, Virgilio Godoy Reyes of the Independent Liberal Party (PLI), tried to withdraw from the race more than a week ago when his party voted to pull out of the election. But the Nicaraguan Electoral Council insists he is still running because PLI did not officially present its withdrawal petition until Oct. 30, which the council said was too late.
PLI's vice-presidential candidate, Constantino Pereira, who is considered to think more favorably of the Sandinistas than Mr. Godoy, has declared he will not withdraw his vice-presidential candidacy. He has called on partisans to vote for him on Nov. 4.
Almost simultaneously, in a chaotic scene reminiscent of old-fashioned banana republic political farce, the pro-Sandinista head of the Democratic Conservative Party, Clemente Guido, tried to preserve his candidacy by dissolving his party's convention.
With the aid of 200 young members of the party, he closed the convention when an overwhelming majority of party members seemed on the point of voting in favor of abstaining from the election.
Conservative Party leaders favoring electoral abstention charged that party youth groups acting with Guido are heavily infiltrated by members of Sandinista state security and of JS 19, the official Sandinista youth organization.
At time of writing, party chief Guido maintained he would still present himself as the party's candidate on Nov. 4.
In a more conciliatory gesture, however, the San-dinistas have opened a ''national dialogue'' with leaders of 33 groups representing a wide array of organizations with both pro- and anti-Sandinista views.
Opposition leaders said they would not take part in the elections without such talks, which would have laid down the ''rules of the game'' for continued existence of opposition parties, the press, and the private sector.
Although the Coordinadora alliance of the main opposition parties is participating in the dialogue, opposition leaders are skeptical of the talks called only two or three days before elections.
The difficulty in judging the fairness of the elections, many observers say, is that the electoral picture cannot be reduced to simple black-and-white terms. But Nicaragua has become such a politically charged issue internationally that many governments and political organizations seem intent on issuing either blanket indictments or positive assessments of the electoral process keyed to whether they favor the Sandinistas or the Reagan administration.
Most Western observers interviewed by this writer concur that the campaign, which officially opened Aug. 8, began to heat up after a slow start. From mid-August until the beginning of October, opposition parties were subject to considerable harassment by the Sandinistas.
Perhaps the worst treatment was borne by Arturo Cruz Porras, potentially the most politically threatening candidate to the Sandinistas, during various rallies throughout the country at the end of September.
In August, crowds that gathered to support Cruz, the PLI, and other parties were attacked by Sandinista-organized mobs, which Sandinistas said were manifesting spontaneous ''popular anger.''
People distributing official campaign literature or painting slogans on walls were attacked and the literature itself was torn down. Also, middle- and lower-level campaign workers were intimidated. Sometimes they were arrested.
One (non-US) Western diplomat counted some 114 press articles as having been totally or partially censored between Sept. 1 and 23.
Mr. Cruz withdrew from the electoral campaign. But the electoral process became freer in October for both the press and opposition candidates, most observers say.
The Sandinista electoral record has been extremely varied - one that many electoral observers, especially those who arrived in Nicaragua for the first time a few days ago, may find hard to put into perspective.
Political harassment during the campaign, according to observers interviewed by this writer, was never comparable to the systematic brutality of truly authoritarian regimes such as Nazi Germany, Fascist Italy, or most communist countries.
The most accurate comparison would probably be with the somewhat haphazard harassment prevalent in Nicaragua under former dictator Anastasio Somoza Debayle and other old-fashioned banana republic-style dictators.
Moderate Western electoral observers familiar with elections in El Salvador, Zimbabwe, and Guyana say that electoral conditions in Nicaragua are certainly no worse than conditions in those countries, whose elections were endorsed by the US and other Western countries.
These observers also assert that although there have been no known deaths in Nicaragua's campaign, any left-wing candidate foolhardy enough to have run in nearby El Salvador's elections would probably have been assassinated.