Coalition Leader

A modest, thin, social democrat, Guillermo Ungo heads the umbrella Democrat Revolutionary Front comprising leftist guerrillas and political groups ranging from left to center. For most of his 49 years an advocate of nonviolent change, he says abuses by the military drove him to the violent path.

Ungo is considered certain to belong to a new government, should the opposition seize power or should a coalition form between the two camps.

The former law professor at the Jesuit-run Central American University has drastically changed his style of living in the months since he took up exile and leadership of the front. He now moves from sessions with guerrilla commanders at secret sites to press conferences and political contacts across the Americas and in Europe.

The son of a print shop owner, he lost his first political job when the military barred him from the National Electoral Council. In 1969, he joined a local version of European social democratic parties and quickly became secretary general.

Ungo ran for vice president in 1972 on a ticket with Jose Napoleon Duarte and like him was driven into exile when the military stepped in to block them from power. He urged his party to try the electoral route again in 1977, and once again the military blocked the expected victory of this second reformist coalition.

Following the 1979 coup by reformist junior officers, Ungo joined the broad-spectrum junta only to resign after three months, saying older conservative officers had regained control and stepped up repression.

Ungo denies that he is a mere figurehead for the Front, serving to lend respectability to more radical leftist guerrillas. The alliance, he says, is "a marriage of convenience" built on "a foundation of love." Communist Veteran

Shafik Handal, 50, the son of Palestinian Christian immigrants, is secretary general of the outlawed Salvadoran Communist Party. He joined it 30 years ago and has spent much the time since in jail or exile.

The biggest boost to his popular recognition came in the 1960s, when the ruling military pasted his picture on walls across the country labeling him El Salvador's Fidel Castro. Through the 1970s, both he and Castro pressed for the Salvadoran party to seek respectability and participate in elections.

More radical groups displaced Handal's party on the left until the Communists joined in guerrilla warfare last year, forming their own relatively small force.

Handal's main contribution to the opposition effort seems to be as contact man with ruling Communists worldwide. His recent tour through capitals from Moscow to Hanoi, according to a U.S. white paper, was a major arms-gathering expedition. He denies the charge. Rebel Chiefs

The most prominent leaders of the several guerrilla forces, now united at the command level if less so in the field, are Ferman Cienfuegos and Salvador Cayetano Carpio.

Cienfuegos has been head of the guerrilla movement with the longest history, since September called the Armed Forces of National Resistance. He took over from founder Ernesto Jovel, who died in a plane crash. Cienfuegos is from a well-to-family, educated at a Jesuit high school and an early member of the Communist Youth. He went underground 11 years ago, although he has been seen at least once in Cuba.

Cayetano Carpio, is a longtime Communist and former bakery employe committed to proletarian revolution. The younger Marxists tend to respect him as "the old man" but do not necessarily accept his views. He is coordinator of the Farabundo Marti National Liberation Front, which is named for a still earlier Communist.