Well, I hadn't taken a look at Colorado recently, and figured that I'd go for an extreme. I wanted to see if I could make five solid Democratic districts. It's possible, but is abhorrently ugly and completely ignores communities. I defined "safe" as the 55% for Dems in last year's statewide elections. This necessitates splitting the Denver region six ways. The five Dem districts basically take in everything that isn't a GOP stronghold. Primaries might be ugly, with extreme regional differences, but these districts aren't going GOP. Politically, they're about in the middle of the Perlmutter and Polis districts, so something between 60% and 63% Obama. Incumbents don't really play into the picture, so I'll just give images and numbers.
And just to be clear, I'm not actually saying this is a good thing; my idea of what we should have in Colorado is two safe Dem seats, three lean Dem and two safe GOP. If there were a way to do this cleanly, though, I'd just say go for it.
The State:
The Denver Region:
GOP Sink 1:
34.5% Dem, 64.6% GOP
85.9% White, 7.3% Hispanic
GOP Sink 2:
29.5% Dem, 70.5% GOP
80.2% White, 13.0% Hispanic
Dem Seat 1:
55.6% Dem, 44.4% GOP
56.7% White, 24.0% Hispanic
Dem Seat 2:
55.5% Dem, 44.5% GOP
69.8% White, 22.5% Hispanic
Dem Seat 3:
55.4% Dem, 44.6% GOP
70.1% White, 23.0% Hispanic
Dem Seat 4:
55.1% Dem, 44.9% GOP
80.6% White, 13.7% Hispanic
Dem Seat 5:
55.1% Dem, 44.9% GOP
73.7% White, 18.4% Hispanic