I think it would be really hard to start out at that distance and keep it up every day. The first day isn't so bad, but it'll wear on you as the week goes on.
+1, I think it will be brutal for the first few weeks. Your cardio is likely not ideal given the heavy smoking. If at all possible, drive in part of the way and bike the rest. Option #2 would be to do the entire commute but start off doing it 2 days a week and add 1 day per week as you build up your endurance. When I started out commuting I had ~9mi in each direction and I was definitely slower on Friday then I was on Monday :-).
By all means, go for it but ease into it. Pushing too hard at the beginning is a good way to injure yourself.