I'm a marathoner too; but usually only if it's involved with triathlons. I've completed 4 Iroman world championship races (DNF'd one
) in Kona and am thinking about starting to train again since I haven't done one since '03. It's so time consuming though and my dh is NOT into any type of exercise at all, so it's all me.
Just start out slow and enjoy the race; if you've trained well, you shouldn't have a problem finishing. Good luck (and don't forget to hydrate!)