"The Democratic-controlled Senate" and "the Republican-controlled House of Representatives" do that "payroll tax cut" they've been fussing over.

But I just want to talk about CNN's grammar. In an effort to avoid saying "Democrat" for "Democratic," CNN has said "Democratic" when it makes no sense. "Democratic" is only an adjective, and Democrats are annoyed when Republicans use "Democrat" as an adjective instead of "Democratic," but when you want a noun, you need to say "Democrat."

I could imagine thinking an adverb was needed with "-controlled," but then it would be "Democratically-controlled" and "Republican-controlled" would lack parallelism. But you don't use an adjective to modify an adjective, and
"-controlled" is obviously an adjective.

CNN is overcorrecting itself out of fear of lapsing into the conservative shibboleth "Democrat" for "Democratic."

ADDED: Test my point with another example, used with "-controlled": A school controlled by parents could be called a "parent-controlled" school. You wouldn't dream of calling it a "parental-controlled" school. You might consider "parentally-controlled" (and wouldn't you drop the hyphen?). "Parentally controlled school" wouldn't be grammatically wrong, but it would have the wrong meaning. It would be a school that was controlled in a parental fashion by who-knows-who, not a school controlled by parents.