Just returned from a weekend at Moraine Park in Rocky Mountain National Park. The ranger at the check in station told me that there had been bear sightings in the general area, and that during the previous season in 2015, there were sightings nearly weekly during the camping season in Moraine Park. And while hiking, there was evidence of bear presence in the form of scat seen near the trail as well as near the amphitheatre for the CG.
In the campsite adjacent to ours, there was a hybrid trailer. The residents of it left a cooler out when they went to go fishing. A park ranger patrolling around, stopped at their site, confiscated the cooler, and issued a "violation notice". When the occupants got back, they found the notice and missing cooler. The occupants were able to retrieve the cooler by going to the ranger station there at the entrance. No idea if they had to pay a fine, and if so, how much.
There are approximately 35-40 bears within the park borders. An article in the Fort Collins Coloradoan from 2015 found that the black bear population was booming in an area of around 240 sq miles from the Estes Valley to the Poudre Canyon to the north. The same article cited bear encounters in town in Fort Collins and Loveland, and I am personally familiar with the frequent sightings in Fort Collins during my employment there. In all of Colorado, there are approximately 19000 black bears, according the Colorado Department of Parks and Wildlife.
Weekend before last, we were at Camp Dick/Peaceful Valley, which is fairly close to Olive Ridge (all of which are wonderful campgrounds, by the way). Host at Camp Dick, where we stayed, said there had already been bear sightings in the area and evidence of their presence along the trails. In all 3 of these CG, there are bear storage vaults for placement of food and related items. Same thing within RMNP CG; numerous bear storage vaults.
In both trips over these past 2 weekends, tent campers have outnumbered folks in trailers/hybrids/motor homes. In the cases that I observed, these tent campers used safe practises and put food items in the storage vaults. Following the rules posted at ALL of the campgrounds that I've ever stayed at in the Colorado mountains is the best, most practical means of lessening the chance of a bear encounter. You stated that you've camped in Colorado before with a PUP and no problems. Just follow common sense practises with your hybrid, and you'll likely not encounter problems.
If you're looking for places to stay within 4 hours of Denver, that's a very broad area, and encompasses most of the urban corridor of I-25 from Cheyenne/Laramie WY area down to Raton Pass, east to Kansas and Nebraska, and a goodly portion of the mountains on both sides of the Continental Divide. A lot depends on whether you prefer amenities (you stated you were looking for places with restrooms as well as utilities) or can get by with less.
Olive Ridge does not have amenities as you described. Vault toilets and common water outlets (non-threaded IIRC). Neither do any of the CG I mentioned above; Moraine Park does have some "comfort stations" with flush toilets however.
There are quite a few State Parks, County Parks, and commercial parks within that 4 hour range you're looking for. If you could narrow down a specific area, and what you're looking to do while out here, that would be helpful. Also, how much time do you have available? Also, keep in mind that for August, you're likely going to need reservations at a goodly number of locations, as they are already booked/booking. There are some first come/first served locations, but you'll need to search them out. Commercial parks may be a bit easier to get reservations, depending on location.
