have no more than a snowball's chance in hell

To be completely impossible or incredibly unlikely; to have no or very little chance (of something). That party doesn't have a snowball's chance in hell of winning an election in this part of the state. I knew I wouldn't have more than a snowball's chance in hell of getting in, but I sent in my application anyway. Well, we have no more than a snowball's chance in hell if we have to compete against some mega corporation like that!