Some cats are very resilient, and territorial. I've known one that was about 10lbs and had no problems scaring off raccoons 2-3 times his size. If yeu're aggressive enough, it's not a problem.
Others are very cautious, I knew another cat who was just very jumpy, always ready to run, and didn't worry about territory or food... mostly because he just made friends with EVERYONE nearby and got bits of food from everyone (ended up a rather tubby kitty).
On another note, there's another cat I know of that probably weighs more than most raccoons, and it's NOT fat o.o It's like a 26lb cat that's like pure muscle, thing is scary XD
Last I'd heard, the first one died at 16 due to organ failure, but not to anything like raccoons, foxes, or other things known in the area, despite being an outdoor cat (though he had to be kept inside for months at a time due to being injured in fights because he was so territorial). The other two are still going strong to my knowledge, also both outdoor cats of 15+ years.
The thing people fail to realize, is that cats are very powerful and dangerous for their size. As predators go, pound for pound, cats are some of the most deadly there are out there. They may be small, but they can generally take care of themselves, even against a larger opponent, unless that larger opponent is both substantially larger (like 100lbs+ coyote or something) and starving (as in they won't back down from a fight because they're about to die themselves anyway), the cat will generally make the other back off.
Most cats are also smart enough to know to be cautious around cars and traffic as well; it's far more common for a dog to get hit by a car than a cat, though sadly the latter does still occur as well.
Generally, outdoor cats aren't at THAT much higher risk, but they do need to be looked after, and certain areas with more vicious wildlife yeu need to be careful about. If others such as raccoons and such are well fed, they won't likely bother a cat. If they think the cat's food is the only way to survive, then they can fight back, which can turn into a very bad situation. If yeu keep extra food out in an area like the roof for raccoons and such, they'll generally leave cats alone.
Or if yeu're really scared, but still want an outdoor cat, get a pet fox or lynx, they're large enough to take care of themselves, and have a very similar temperament to a cat as a pet. They do tend to be more expensive, difficult to keep, and harder to find a vet that knows how to treat, however, and many areas require special licenses for such. Also, foxes think they're cats rather than dogs... they like to jump up on furniture, counters, etc... except they are notably larger and don't realize that they can and will knock down anything nearby in the process.
In any case, there are also many cats who like being indoor cats too; food, shelter, love, if they get all these things, they can live a luxurious lifestyle and never feel the want to be outdoors, unless they were raised as outdoor cats in the first place, in which case it's near impossible to keep them in, and they won't listen anyway.
I've seen some cases where cats will be willing to walk on a leash as well, they just take substantially more training than a dog for that is all, since they really don't like listening XD