Asked specifically about his and Channell's involvement with the rebel office, Miller, a former Agency for International Development official, declined to discuss "any client matters."

Ernesto Palazio, the chief UNO representative in Washington, refused Wednesday to discuss his organization's financial backers. "We are a guerrilla organization, and therefore we cannot publish a balance sheet or provide any other public financial data, as if we were General Motors, " Palazio said.

Independently of the rebels, Channell orchestrated simultaneous media campaigns on behalf of the contras through several conservative committees and groups.

Using two groups, Sentinel and the Anti-Terrorism American Committee, Channell bought extensive television time for pro- contra commercials.

In the weeks before a crucial House vote on the Reagan administration's $100 million contra aid package alone, Channell spent more than $200,000 on a nationwide television campaign to persuade at least 11 key Democratic opponents to support the aid package.

Some $50,000 of the money was spent in Maryland, where Democratic Rep. Michael Barnes, an influential contra aid critic, lost a primary campaign. The commercials mingled a photo of Barnes with pictures of Fidel Castro, Daniel Ortega and other Communist leaders.

Channel also bought several full-page ads in The Washington Times and Baltimore Sun portraying Barnes as a dupe.

Several congressional candidates targeted by Channell raised questions about the source of his funds.

"During the campaign we kept wondering who was funding this media campaign against us, and we could never figure it out, " Barnes said. "Now the question is much more pertinent in light of the diversion of the funds and the fact that it is still an unresolved question how that money was used."

Sources said that in private testimony before the House Foreign Affairs Committee, CIA Director William Casey said Wednesday that he did not know how the diverted money had been spent.

When congressional races began in earnest for last November's mid-term election, Channell targeted key candidates opposed to Reagan's contra policies. Again, in the Maryland Senate campaign alone, Channell spent $90,000 on commercials blasting Democratic Rep. Barbara Mikulski as too liberal.

Mikulski's opponent, Republican Linda Chavez, a former White House aide on Central American affairs, found Channell's advertisements so abrasive that she publicly requested that he end the campaign. Chavez, who lost to Mikulski, wrote an opinion piece in The Washington Post recently, denouncing Lt. Col. North as a "zealot" who had damaged "the Reagan Revolution."

A public relations aide to Channell said "millions and millions of dollars" were spent on the contra television campaign nationwide.

Beyond seeking to influence public opinion, Channell, in coordination with North, carried out a direct campaign on Capitol Hill.

Among the lobbying efforts sponsored by Channell was the Council for Democracy, Education and Assistance, which was established last January by conservative public relations specialist Robert W. Owen. Owen had served as North's private intermediary with the contras during the period when U.S. officials were prohibited by law from aiding the contras. Owen declined to answer questions before the Senate Intelligence Committee Monday.

Channell donated at least $66,000 to the council for congressional lobbying in the House alone, according to House records.

Using Channell's funds, the council hired an influential human rights activist, Bruce Cameron, to design the pro-contra lobbying campaign that culminated in June with House approval of the $100 million aid package, the House records show. Cameron was out of the country Wednesday and could not be reached for comment.

In a parallel effort, Channell funded a speaker's bureau, sending Nicaraguan exiles on journeys throughout the United States to persuade audiences face-to-face of the legitimacy of contra aid.

The speakers included Nicaraguan rebel representatives in the United States including Bosco Matamoros of the Washington office, Mario Calero of New Orleans, who is a brother of contra leader Adolfo Calero, and Teofilo Archibald, a Miskito Indian. Channell paid the speakers' travel expenses but did not pay them for their appearances.