Gunfire rattled in the distance as heaving, jostling lines of people stretched from the single door of the San Vicente Community Center both ways around the block, and soft-drink sellers pushed their wares to the sweaty crowd intent on getting inside to cast their ballots.

The scene was repeated in a number of El Salvador's towns today. That is not to say that all of those who lined up actually got to vote, or that some of them did not vote twice.

There were problems with every aspect of the mechanics, from nonexistent transportation through invisible ink that rubbed off the fingers it was supposed to identify permanently, to inadequate facilities for all those who wanted to vote.

But in San Vicente and in many other cities, there was almost too much voting, and despite the almost total lack of transportation from the countryside into cities, people found ways to get to the polls. Even some of the guerrillas operating along the highway leading into this provincial town struck a nonchalant attitude for the day.

A group of guerrillas wielding M16s and a Chinese grenade launcher halted all passers-by a few miles south of Santo Domingo, 25 miles northeast of the capital, on a deserted stretch of road under construction. After a few tense moments aiming their weapons at a carload of reporters, they relaxed and chastised us for failing to follow procedures.

"We have orders to let pass only cars with a white flag," said the leader, who called himself Diko. We promptly attached to the windshield the only white objects we had along, a pair of socks.

The guerrillas said they were letting voters pass "because many are afraid not to vote," but villagers waiting anxiously a mile along the road told us the guerrillas would not let them through. No direct acts of intimidation were seen, but the guerrillas' presence seemed to be enough to prevent them from going to vote.

"There are about 2,000 of us here who want to go vote and we can't," said one well-dressed woman indignantly.

The only road from the west to the eastern provincial capital of Usulutan had new brush barricades and ditches today and was fully blocked at the blasted Golden Bridge over the Lempa River. Intense fighting between soldiers and guerrillas at San Marcos Lempa on the eastern side of the river around 11 a.m. climaxed in the guerrillas' capture of a 12-man Army patrol.

Soldiers guarding the bridge on the western side of the river got the word by radio.

"Were they alive?" one soldier asked into the speaker. "They were alive," he announced to the others. They all shook their heads. There had been heavy fighting in the area since early yesterday. "No voting today in Usulutan," one said.

The scarcity of voting places compared to previous years made the size of the turnout hard to judge, but endless groups of people were seen walking along highways toward the polling places as early as 6 a.m., an hour before the polls opened.

Guerrillas have been urging people to cast blank ballots as indicators of support for the left, which is boycotting the elections as a farce.

Guerrilla efforts to shut down all public transportation appeared to have been almost totally successful everywhere, however, leaving the roads eerily empty except for a few large trucks hauling voters, Red Cross vehicles carrying international observers and vans, taxis and cars full of journalists.

By midafternoon, each of the 25 voting tables in the community center in San Vicente had counted 250 to 280 voters and the lines had vanished. "People voted in the morning to get home before dark," explained Victoria Galixto de Velasco, president of the provincial electoral board.

Scattered fighting elsewhere failed to dim some voters' spirits. In Cuscatancingo, a working-class neighborhood north of the capital, a middle-aged shopkeeper crouched in the stairwell of the voting place as guerrilla snipers fired over the rooftop. Members of the Salvadoran National Guard answered with a deafening staccato of heavy machine guns and grenade launchers.

"There have been enough people killed in these last two years, as many civilians as military," the man said when the shooting eased. "We hope that this vote will calm down the situation. We hope that."

Many voters spoke of overcoming fear to get to the polls. In the town of Zacatecoluca, an hour's drive east of the capital, Martina Jaime y Reyes, 74, said she had been through many elections but never one that drew as many people as this one.

"Subversives" had knocked on the door of her bakery shop one night, she said. "They told me, 'Don't vote or you die,' but we shut the door in their faces," she said proudly.

A group of Colombian politicians, including Ambassador Hernando Pallau, arrived here by helicopter to view the situation.

"I'm very impressed with all the people," Pallau said.

Rolando Ordonez, a Panamanian member of the Christian Democratic labor federation, Latin American Workers Organization, headquartered in Venezuela, called the vote "a profound success."

In the western provincial capital of Ahuachapan, Camilo Perera Uruena, vice president of the Uruguayan electoral court, said he thought voting procedures looked good but that the jammed voting places did not have enough time to get to everyone.

Political observers from the various parties watched at each voting table and were complaining by day's end of "anomalies" but not of fraud. The black-light machines that were supposed to spot the invisible ink marks guarding against double voting had run down their batteries and barely worked, one observer said.

All the observers charged that the others had been improperly trying to influence voters inside the polling area.

"Yes, yes, I know they say that," said Velasco of the electoral board, her patience worn thin. "But if they all say it, then perhaps they cancel each other out, no?" She smiled. For her, she said, it was "a beautiful day."