Going to Denver 7/19 - looking for good, local and reasoable food.
I love Potager (1109 Ogden St, Denver, 80218). The menu changes seasonally, with the chef working to incorporate local ingredients. It's pricey, but the food (for us) has always been excellent. We had a goat cheese appetizer, colorado lamb chops and steak, and butternut squash ravioli.
If you go on a weekend, get there early---they don't take reservations and it gets crowded (although the bar is a nice place to wait). Also, I believe it's only open for dinner at 5:30pm.
(I just realized you said "reasonable"---this isn't cheap, but it's worth it)