You may find this link to be of interest. I do not like the tone of this "doctoral thesis" a single bit, but you may be able to judge better whether it has any redeming qualities. I would be curious to see the bibliography.
The Institute for Social Research is, by the way, a Marxist research institute. Its original founder, Theodor Adorno, was a prominent Communist from Frankfurt who knew Schmitt personally and professionally. They hated each other.
The webpage seems to make reference to his famous early paper Der Begriff des Politischen where he makes the argument that all political groupings are organized along friend/enemy lines. Neither the 1927 or 1967 editions make any reference to Jews or Judaism.
I'd like to see more of ISR's evvidence.