July 23 (Bloomberg) -- A second Federal Communications Commission Democrat voted against Sirius Satellite Radio Inc.'s plan to buy XM Satellite Radio Holdings Inc., leaving the merger's fate to the sole undecided Republican.

Democrat Jonathan Adelstein, who voted against the $3.5 billion merger today, said in an e-mailed statement that the combination would create ``a monopoly with window dressing.'' Fellow Democrat Michael Copps already voted no.

Two Republican commissioners, Chairman Kevin Martin and Robert McDowell, have backed the merger, leaving the outcome to the agency's fifth member, Deborah Taylor Tate, a Republican who has yet to vote. A telephone call to her office wasn't returned. Reuters reported Tate is nearing a ``yes'' vote, without saying where it got the information.

``Commissioner Adelstein would only cast a dissenting vote once it was fairly clear that Commissioner Tate would support the deal,'' Paul Gallant, a former FCC official and Washington- based analyst with Stanford Washington Research Group, said in an interview. He continues to predict approval.

Commissioners, who face no deadline for a decision, vote electronically at the time of their choosing.

Traditional radio companies led by the National Association of Broadcasters oppose the merger, saying it will create a harmful monopoly. Sirius and XM, the only two pay-radio companies, told regulators their union would bring consumers more programming at a lower cost.

Price Freeze

The companies agreed to freeze prices for three years, to sell channels in smaller packages and to allocate 8 percent of their channels for use by educational and minority broadcasters.

Antitrust authorities at the U.S. Justice Department cleared the deal in March, saying competition from music sources including MP3 players and traditional radio would keep the combined company from raising prices.

Sirius, based in New York, dropped 1 cent to $2.37 at 2:03 p.m. New York time in Nasdaq Stock Market trading and had declined 21 percent this year before today. XM, based in Washington, rose 51 cents to $9.62 and was down 26 percent.

Sirius is offering 4.6 of its shares for each of XM's. The companies first proposed the combination in February 2007.

Adelstein had sought a six-year price freeze, and for the companies to allocate 25 percent of their spectrum for educational and minority broadcasters. He also wanted requirements that the radios be capable of tuning into both services as well as terrestrial broadcasters' digital channels.

``I was hoping to forge a bipartisan solution that would offer consumers more diversity in programming, better price protection, greater choices among innovative devices and real competition with digital radio,'' Adelstein said in his statement. ``Instead, it appears they're going to get a monopoly with window dressing.''

FCC spokesman Robert Kenny said the agency had no comment on Adelstein's vote.

To contact the reporter on this story: Todd Shields in Washington at tshields3@bloomberg.net

Last Updated: July 23, 2008 14:05 EDT