I am going to take a scholarly objective here. 
California is the planet's ninth largest economy (at least, I think that it still is).  They could survive on their own. But only contingent on the condition that I get conjugal visits with Dereperez! (Love 'ya Derek!)
Texas was a republic (its own nation) from 1836-1845.  They keep threatening to secede. Let them put their money where their mouth is and try making it on their own. I think that they could do it. 
Hawaii was once its own kingdom, but I think it is simply too nice a place to give up. Hawaii stays a state!
Maine is very much like its Canadian neighbours, with an independent way of thinking, and a bit of maritime stubbornness. While I would miss the rocky beaches, beautiful lighthouses, and the rural, quiet, beautiful interior (and the lobster too!) I think Maine could easily join Canada, and fit right in with New Brunswick, PEI, Newfoundland, and Nova Scotia. 
As for some of the other states mentioned...
Michigan...stays.....I have family there (in the Detroit suburbs), and I do like Mackinac Island! 
New York...stays...I live there, and while I have no problem with independence, I would be very much for joining Canada. 
Illinois...stays...We get to keep FrankFrank and Chicago! 
Mississippi...stays...even though it is one of the most impoverished states, its cultural impact on the South cannot be denied. 
Massachusetts...stays...
we get to keep Provincetown! 
Oregon and Washington...both stay...too many natural resources to give up (and I want to keep Bort!)
Kansas...stays...yes, it's flat and boring to drive through, but good farmland (and hung farm boys) are an important commodity! 
Alabama...stays...I could tell you some hair-curling stories about what it was like when I spent time with my cousin who moved to Tuscaloosa for his job...but it is also a state with great natural beauty and a deep history of two races. 
Montana...stays...the skies are clean, the land is huge, the cowboys are stunning, and the scenic beauty is unmatched! 
Idaho...stays...potatoes and resources...need I say more? 
The Dakotas, The Carolinas, and the Virginias...all stay...how else are American children going to learn geography?