1
general::
Also, pull wires. Use one's influence, as in By pulling strings he got us house seats to the opening, or His father pulled some wires and got him out of jail. Both terms allude to manipulating a marionette. The first dates from the second half of the 1800s, the second from the early 1800s.
American Heritage Idioms
2
general::
Phrase(s): pull (some) strings [and] pull a few strings
to use influence (with someone to get something done). • I can get it done easily by pulling a few strings. • Is it possible to get anything done around here without pulling some strings?
McGrawhill's American Idioms And Phrasal Verbs