In an election year that has been dominated by discussions of candidates' religious faith, perhaps no candidate's religion has been more controversial than Sen. Obama's Oprahism.
Speaking to supporters at the University of Iowa, the Illinois senator devoted his entire speech to his religious faith but mentioned Ms. Winfrey only once by name.
"My religion is a personal matter to me," Sen. Obama told his followers. "Having said that, let me make this clear: I have accepted Oprah as my host."
Later in the day, Ms. Winfrey toured the state with Mr. Obama and, in a stunning demonstration of her influence, briefly caused a solar eclipse.
"Sun and moon, do my bidding!" she roared, raising her hands above her head and delighting the crowd with the celestial display.
"Oprah is without question the most powerful force in the election right now," said Carol Foyler, 45, an Obama supporter from Cedar Rapids. "I'd like to see Bill Clinton do that."
Davis Logsdon, who studies the interrelation between politicians, religion and talk-show hosts at the University of Minnesota, said that Sen. Obama's worship of Oprah Winfrey puts him in the mainstream of American theological belief.
"More than 30 percent of Americans currently define themselves as Oprahists," Mr. Logsdon said. "And that number is higher during sweeps."
Elsewhere, the CIA created more controversy today by acknowledging that it accidentally returned several interrogation tapes to Blockbuster.