Freedom’s Watch, the political advocacy group once hailed as the conservative answer to MoveOn.org, may be the latest casualty of the economic downturn.

There was a time when Sheldon G. Adelson seemed famous for his anonymity. He built casinos, backed politicians and contributed millions of dollars to a variety of causes but stayed behind the scenes.

Freedom’s Watch was ballyhooed last year as the Republicans’ answer to MoveOn.org. It was to be a grassroots conservative group bankrolled by billionaire conservatives like Sheldon Adelson of the Sands Corp.

Sheldon Adelson, the New York Times writes today, “may well be the richest American that most people have never heard of.”

But Republicans certainly know the name. Adelson, who personally cleared $500 million when he sold the Comdex trade show to Softbank and has since made millions more in the casino & convention industry, is a major donor to GOP causes.