Herman Cain proudly said he stands with the billionaire Koch brothers on Friday, saying he was “their brother from another mother.”

At a speech in Washington to a conservative organization funded by David H. and Charles Koch, Mr. Cain mocked an article in The New York Times on Friday about his relationship with them.

“I’m proud to know the Koch brothers,” Mr. Cain declared at the conference of the Americans for Prosperity Foundation, the Tea Party group co-founded by the brothers. “This may be a breaking news announcement. I am the Koch brothers’ brother from another mother. Yes! I’m their brother from another mother, and proud of it.”

As he made the statement, David H. Koch stood up and pumped his fists in the air, a big smile on his face. The Times article reported on the connection between Mr. Cain’s chief of staff, Mark Block, and the foundation, which the Koch brothers have helped to finance.

The article noted that “because the Cain campaign’s core staff members are veterans of Americans for Prosperity — Mr. Block, his deputy manager, the senior economic adviser — some critics on the left suggest that despite Mr. Cain’s image as an outsider, his candidacy is in effect a mouthpiece for the corporate interests of the Koch brothers.”

Mr. Cain did not make any direct statement about the sexual harassment allegations that have dogged him this week. He did note, with a smile, that “I’ve been in Washington all week, and I’ve attracted a little bit of attention.”

Instead, Mr. Cain offered his standard stump speech, in which he called for clarity in foreign policy, a new tax system based on his “9-9-9″ plan and a revamped energy policy in which the country does far more exploration of all sources of energy.

Anticipating opposition to the latter, he got his biggest applause by declaring that the Environmental Protection Agency “needs an attitude adjustment.”

“They work for us. We don’t work for them!” Mr. Cain said. “Attitude adjustment time at the E.P.A.!”