LIMA, PERU, JUNE 7 -- Boosted by his winning performance in a candidates' debate and the tacit support of the Roman Catholic Church, novelist Mario Vargas Llosa has gained ground on opponent Alberto Fujimori in recent weeks, and some analysts see Sunday's presidential runoff election as a dead heat.

A month ago, surveys showed that Fujimori, a 51-year-old former university president, held a comfortable lead over Vargas Llosa. But pollsters say they have detected a shift and agree that Fujimori's lead has shrunk. A poll this week by a research firm, Datum, showed the two candidates tied, but rural areas -- which gave important support to Fujimori in April's first-round vote -- were not included.

Vargas Llosa, 54, finished first in the April balloting. But Fujimori was considered the favorite in the runoff because his middle-of-the-road views are much more palatable to voters who supported the ruling APRA party and other left-leading parties in the first round. Vargas Llosa's conservative economic proposals are anathema to such voters.

A survey showed that Vargas Llosa was seen as the winner of the candidates' only face-to-face debate last Sunday night. As might be expected from an urbane, well-traveled man who is one of the world's most acclaimed novelists, Vargas Llosa was the more polished and eloquent debater. But he also succeeded in highlighting a key theme: that his Fredemo coalition has put together a detailed plan for governing Peru, while Fujimori's Change 90 movement is still vague on its policies and philosophy.

Fujimori drove home his message that Vargas Llosa is the candidate of the rich and privileged, while Change 90 has the interests of the poor majority at heart. But his attacks at times sounded shrill, and the humor and ease that characterize his impromptu campaign stops were absent.

The Roman Catholic Church appears to be playing a key role in Vargas Llosa's rebound. The church seems to see Fujimori's campaign -- which has the overwhelming support of evangelical Protestants throughout the country -- as a threat.

Fujimori is a Catholic, but one of his two vice presidents and a number of Change 90's newly elected congressmen are evangelicals. Some evangelicals have boldly predicted that Fujimori will do away with what they see as official discrimination that favors the Roman Catholic Church over all others.

Last week, Catholic Church leaders staged massive religious processions through the streets of Lima and several other cities, and pastors have spoken to their congregations about the danger that "sects" pose to the nation.