It depends on so many things, mainly the course and how competitive it is.
When I was doing A2 at college in 2006/7 I applied for History and got rejected within a week of sending off my application - my predicted grades werent high enough - even though I got AAC (Lit, History, Law) in my AS Levels. There's no way I'd have met an offer anyway though as I came out with a pretty embarassing BBD (I was supposed to be a straight A student).
Nevertheless, I reapplied this time round after being in work for a while and having a long think about what I wanted to do, and somehow I got an unconditional offer for Archaeology. Despite bad results they took into account my maturity and experience, and Archaeology isn't exactly mega-popular...but I'm still over the moon as I applied as a kind of laugh, I really didn't think I'd get in.
I think in some cases it's harder for college leavers to get into prestigious unis (Manchester is quite prestigious after all) having really good grades, than it is for mature students with other experiences and all-round abilities to - as they're more likely to stick with the course and do well, and not drop out. Seems kind of unfair, but I'm not complaining.