I was wondering is a cea level of 8.8 possibly due to solely being a smoker?

Not likely: Smoking raises the CEA level but usually just double that found in non smokers without cancer. Normal averages 2.5 in women and 3.4 in men. In smokers, the average is 4.9 and 6.2 so 8.8 is worrisome but the more you smoke, the higher the CEA. You should have it rechecked, and if persistently elevated you need to be evaluated for a malignancy. Importantly, you need to stop smoking immediately!

Hard to tell.: The CEA is one of our non-specific tumor markers. I would not attribute its elevation solely to smoking. This marker is associated at least with gastrointestinal cancers, and its elevation should be considered in that respect.