The Rev. Ted Haggard resigned as president of the 30 million-member association Thursday after being accused of paying the man for monthly trysts over the past three years.
Haggard, a married father of five, denied the allegations, but also stepped aside as head of his 14,000-member New Life Church pending an investigation.
The acting senior pastor at New Life, Ross Parsley, told CBS affiliate KKTV-TV of Colorado Springs that Haggard admitted that some of the accusations were true.
"I just know that there has been some admission of indiscretion, not admission to all of the material that has been discussed, but there is an admission of some guilt," Parsley told the station. Parsley added that the church remains "100 percent for him."
In an e-mail addressed to church members about Haggard, Parsley wrote, "It is important for you to know that he confessed to the overseers that some of the accusations against him are true. He has willingly and humbly submitted to the authority of the board of overseers, and will remain on administrative leave during the course of the investigation," CBS affiliate KCNC-TV in Denver reports.
In a statement, Haggard said, "so that the overseer process can be allowed to proceed with integrity. I hope to be able to discuss this matter in more detail at a later date. In the interim, I will seek both spiritual advice and guidance."
Carolyn Haggard, spokeswoman for the New Life Church and the pastor's niece, said a four-member church panel would investigate the allegations. The board has the authority to discipline Haggard, including removing him from ministry work.
The allegations come as voters in Colorado and seven other states get ready to decide Tuesday on amendments banning gay marriage. Besides the proposed ban on the Colorado ballot, a separate measure would establish the legality of domestic partnerships providing same-sex couples with many of the rights of married couples.
Church members were stunned by the allegations.
"It's political, right before the elections," said Brian Boals, a New Life member for 17 years.
Church member E.J. Cox, 25, called the claims "ridiculous."
"People are always saying stuff about Pastor Ted," she said. "You just sort of blow it off. He's just like anyone else in the public eye."
The accusations were made by Mike Jones, 49, of Denver, who said he decided to go public because of the political fight over the amendments.