The Concept
A Champion is not someone who likes you. A Champion is someone who has power and is willing to use it for you.
You must 'Test' them. Ask for a micro-commitment that requires them to spend social capital.
The Test
"Can you get me the Org Chart by Friday?" or "Can you stick your neck out and schedule a meeting with the VP?"
If they say no, they aren't a Champion. They are a Coach (or a waste of time).