KAMPALA, Uganda — As storm clouds brewed in the near distance, about 1,300 people gathered at the grassy Makerere University sports grounds here for a special Sunday afternoon rally and prayer service that, its organizers said, was to discuss homosexuality, witchcraft, corruption and the fear of violence leading up to the country’s presidential election next year.

The guest of honor, Lou Engle, an American evangelical from Kansas City, bowed up and down from his knees at the front of the stage.

Mr. Engle, who helped found TheCall Ministries, a prayer group that focuses on moral issues, arrived last week in Uganda, where TheCall has opened a new chapter. His trip comes amid a heated debate throughout the country over a bill that would ban advocacy of gay rights and suggests the death penalty for homosexuals who have AIDS and engage in sexual relations.

Homosexuality is already illegal in Uganda, as in several other poor African nations. Last fall, Uganda’s Parliament began discussion of the sweeping bill, which has brought threats of aid cuts to Uganda, and has focused attention on several American pastors and politicians who have come here and offered themselves as experts on what they consider the scourge of homosexuality.