With today's announcement, she has 'set the wheels in motion' for a run for the presidency. [=she has begun to run for president]
You could almost see the 'wheels' turning in his head. [=you could almost see him thinking about how to do something]
They hoped that the tax cuts would 'grease the wheels' of the economy. [=would help the economy work better]
(..) You're the one that put it in the visor. While it's on the table, I haven't had a turn in quite some time. Oh, no, you didn't! Yes, I did. Hands on the wheel at least, okay? - We're all gonna die! - Pipe down. Didn't that prophecy say you're gonna make it till at least ? (..)2013 Percy Jackson: Sea of Monsters