What would happen if you tried and look like a complete idiot? Would that be so bad that you wouldn't take the risk if you could win so much from that situation potentially? Even if he says no you at least made a step to improve your situation, which would be a success! If someone says no they say no but thats it. Believe me, I made a fool of myself so many times in my life! But nothing bad ever happened from doing that. its really not so bad. You can tell yourself "okay, at least I tried."

Once I asked a guy out I was sure all the women were running after him (and they were) and I had no chance. It took me a long time until I had the courage to ask him. but he was leaving the country so I thought I have nothing to loose because if he says no he'd be gone soon and I won't be reminded of that shame. and it was like my last chance to ask. But he said yes and we met. we did not become a couple but he wanted to follow me home. so I think it was some kind of success because I realized I did have a chance and I wasn't as repulsive as I thought I were.
Of course I have also more awkward stories I could tell you. I just want to say that asking is better than sitting at home alone feeling depressed. Its like buying a lottery ticket.