Fort Collins does get some good snowstorms and occasional brutally cold days but I'd guess it's more mild than Chicago area. We don't get much rain or humidity; most of the Front Range is semi-arid (less than 15 inches of precip. a year). So, the effect is a milder climate even if the temperature doesn't seem to indicate (i.e. would you rather bike when it's 30 deg. and calm/sunny or 40 deg. and windy/raining?).
Just about every road in Fort Collins has a bike lane or adjacent MUP and there is a huge cycling community.
Downtown area (aka "Old Town") is covered in bikes, in part because of the Colo State Univ. student population. The rest of the city is very bike friendly as well, I don't know one person who doesn't bike regularly.
If you're 'round these parts, check out the Bike Library on Walnut Street. They'll loan you a bike and map and you can cruise around and check it out for yourself.