TUPELO, Miss. — To its admirers on the religious right, the American Family Association is a stalwart leader in a last-ditch fight to save America’s Christian culture and the values of traditional families. To its liberal critics, it is a shrill, even hateful voice of intolerance, out to censor the arts, declare Muslims unfit for public office and deny equality to gay men and lesbians because they engage in sinful “aberrant sexual behavior.”

Broadcast on its 192 talk-radio stations, streamed over the Internet and e-mailed in “action alerts” to 2.3 million potential voters, the American Family Association’s pronouncements have flowed forth daily from its sleek offices here in the Deep South.

But now it is doing more than preaching to the choir. This summer, the association has thrust itself into presidential politics by paying for and organizing a day of prayer to save “a nation in crisis” that Gov. Rick Perry of Texas is convening this Saturday. Several Republican presidential aspirants, including Michele Bachmann, Newt Gingrich and Tim Pawlenty, have appeared on a radio program on the group’s American Family network.

The rally, at a stadium in Houston, is expected to draw dozens of the country’s most conservative evangelical groups and leaders, and could burnish Mr. Perry’s national profile and his appeal to religious conservatives as he considers entering the 2012 presidential race.