Actually, starting the generator is the easy part. Keeping the damned thing running - not so much. They pretty much all get carb ice if it's cold enough, and all known solutions involve some sort of insulation around the generator (wooden box, sleeping bag, etc.). I doubt if that'll ever be a problem down there in the Banana Belt, but if it's cold and she's not wanting to run, then is, then isn't, then is, etc. - carb ice!
The little heaters I buy have a 600-watt setting that most any generator will run. Not sure what they're called, but they're the only thing that easily fits under a Champ cowling. Several hardware stores have them here, usually for around $25. Replace the cord with cold-temp as soon as you take it out of the box.
Most all small heaters pretty much ARE lightbulbs, they're just slightly more (or less, depending if you're wanting heat or light) efficient, a little tougher, and have a fan. The fan is the biggie I think - an 1000-watt bulb seems to me like it would melt your top cowl right down onto your frozen-solid oil pan, while the fan keeps everything moving and more-or-less even.
Somewhat unrelated to HOW one preheats, but it's worth mentioning again that a SLOW preheat is important. Use too much heat and/or don't let everything "soak," and you'll end up heating only the outside of your engine. Bad things happen when an oilpump grabs a big glob of frozen oil just as you're clearing the trees at the end of your strip....
Dusty is right on, as usual. A buddy has a Honda i2000 generator that runs a sump pad and mini heater for easy pre-heating his cub. The problems start when it dips under 15 below... The crankcase breather on the Honda starts freezing, and if you don't catch it, the crank seal blows every time. Otherwise, its a great little setup, that can also power other things in camp...
I'm still 110% sold on the old Wham-O White-gas catalytic heaters under the cowl, with a good engine cover. Nice even slow heat, without threat of fire. I'm just too stingy with weight to haul a generator around...
Thanks Dusty, I'll be looking again for a small electric.
Running the gen is no problem for us Southern Gentlemen
When temp dips below PLUS 10 or 20F my doors freeze close & the couch becomes very comfy!
46 Chief Serial #11AC-80
originally N86275 now C-GQHP
46 Taylorcarft in rebuild
Otherwise, its a great little setup, that can also power other things in camp... 
