Source : Webster's Revised Unabridged Dictionary (1913)

Wire-puller \Wire"-pull`er\, n.
   One who pulls the wires, as of a puppet; hence, one who
   operates by secret means; an intriguer.

         Political wire-pullers and convention packers.
                                                  --Lowell.

Source : WordNet®

wire-puller
     n : one who uses secret influence (i.e. pulls wires or strings)
         for his own ends