There's no doubt you can be ready. There're 18 weeks remaining in 2007. Most marathon training schedules for first-times are between 18-24 weeks. Someone in your condition could get ready in 14-18 weeks.
I would suggest you search the web for a training schedules that fits your needs. The Furman First program may be a good one for you to consider.
You should make every effort to pick a schedule that will take you to at least 40 miles per week. Try to incorporate speed work and tempo running.
My only other recommendation is for you to pick a destination marathon rather than a local event. Marathon training takes so much time and effort and you should reward yourself with a mini-vacation!
Good luck and let us know how your training goes.
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