This is how I'd think about it:
- If he didn't like you because of your profile, well, too late, and contacting him again NOW is not really going to cause any damage.
- If he is on the fence, maybe he'll appreciate the interest and follow-up, so contact him again now.
- If he already likes you and is interested, I doubt a follow-up email is going to change his mind.
Call me an optimist - but I think if you strongly feel that this individual could have an impact in your future, then you owe it to yourself to try again.
I don't know what you said on your first approach, so w/o that it is hard to craft a second one. But in general, I'd say something along the lines: "I wanted to follow-up to my previous message... I'm very interested in chatting with you.... Here are the X things that I'd like to pick your brain about, etc..."