I empathise with you, except i've got about 20 crushes at the mo ( well 2 serious ones) :-$ I say go for it... Just be yourself & get chatting, ask for advice on the best places to run, find out where he runs etc... I met my ex-gf ( now my best buddy) a few years ago, when I was working in a store, she kept on coming back & asking questions, it was funny watching her trying to think of another question to ask me. She told me, later, that she thought that I was totally hot & got completely flustered- which is very unlike her. It got to the point where I just asked for her number & the rest is history...one of the best things that i've ever done.