A Senate committee chairman said Sirius Satellite Radio Incorporated has "a steep hill to climb" in showing that its proposed purchase of XM Satellite Radio Holdings Incorporated will not hurt competition in the audio entertainment market. Sirius Chief Executive Mel Karmazin told members of the Senate Commerce, Science and Transportation Committee a combined satellite radio provider would benefit consumers by letting them access both companies" services for a diminished price. "Given the public interest in promoting competition and maximizing a diversity of media outlets, we should be skeptical of claims that new technologies necessarily "change the equation" and provide competition sufficient to restrain monopoly power," said Committee Chairman Daniel Inouye, D-Hawaii. Inouye is the second Senate chairman to express doubts about the merger in as many months. Senator Herb Kohl, D-Wis., chairman of a Senate Judiciary subcommittee on antitrust, aired misgivings about the deal during a March hearing.