Denver vs Seattle vs Portland (live, best, places, life)

[Trytofindmyway]

Hey guys!
So I know the best way to know which fits best with me is to visit these places, but I'm not sure if I have the time/funds to really go out and thoroughly go through these cities.
I currently live in Chicago and plan to move to one of these cities as soon as the new year. (Denver, Seattle, or Portland)
I am a 21y/o single male, and would really like a place with an active nightlife. I am not personally fond of clubs or anything like that, but I can go to a couple bars and have a good time and try and meet new people. If I said meeting a potential girlfriend wasn't on my list, then i'd be lying. I haven't had much luck in Chicago and would love to start fresh.
I would also like to find a nice/safe area close to a downtown so I would not have to drive a lot. Somewhere where its possible to walk to my job or to some shops/restaurants. I could afford no more than $1200 a month.
Also, weather isn't a huge problem for me. I feel like the horrible winters in Chicago have prepared me for whatever lol.
I've been trying to do a ton of research on my own to find a "perfect" place and would love some input from personal experience!
I know I have left out some important factors, so feel free to ask anything so we can figure out a good place together!
Thank you guys!

[dapper23]

Seattle has the most active nightlife out of the three, but it's hard to find a nice place for $1200 near downtown unless you get some roommates.

Portland has the most walkable downtown since it is very compact.

[synapse]

All nice cities. Seattle is probably the most active of the three, and will remind you the most of Chicago, but it's quite expensive, and remote as far as the rest of the USA goes. Portland has an amazing downtown but is a relatively smaller town (less sports, etc.) and is extremely hipster. Both are very rainy, also. I may be biased having moved from Chicago to here, but I think Denver is the closest analogue. It's a big city, but has a walkable downtown; it's got a nice mix of restaurants, bars (it's a great beer town, though not at Portland's level), interesting stores, and museums; the train system runs in a "loop" downtown; and while it gets cold, it doesn't get as cold as Chicago. A lot of single young people are moving here - it's quite popular among millenials, and while it used to have more single men, or at least a reputation for that, it's changed considerably and there's now lots of single females. And, as a plus, unlike Portland and Seattle Denver is also only a two hour flight to Chicago, making visits home a snap.

[Bernard_]

Portland has the most walkable Downtown of the three and a lot of great restaurants and bars. Seattle is the most vibrant and big-city feeling, with some very good concentrated nightlife districts. Denver is probably the sleepiest and sprawliest of the three, but it has much sunnier weather and an up and coming downtown.