Empty suit- google it and get untold numbers of hits.

The remark is everywhere, but I may have got it from Mike Gallagher's remark, widely reported at the time. He made it on Fox on Line, Jan. 16, 2007. Don't know who first said it.

In February, McCain characterized Obama as "eloquent but empty."
ABC News, McCain Rips Eloquent but Empty Obama

Of course "empty suit" is an old business term for an ineffective CEO. Goes back quite a few years.