Agree with the above opinions but I'll take it a step further.
At 12/1 you have little opportunity to hedge until the cup finals unless a longshot faces San Jose in the Western finals. Although much can change between now and April, we have to believe that it would be a Detroit/San Jose finish in the west. The series price would be close to pick providing the Sharks end up with home ice advantage.
Here's why I say you can't hedge before the cup finals.
Let's assume the western finals are between Detroit and San Jose and it goes off at pick 'em. You hedge by betting $30 on Detroit. If the Wings win you net $20. If the Sharks win you now have $40 invested to win $112, (in other words you have the Sharks at 2.8/1).
At this point of the year, I would think San Jose would be a favorite over anyone that comes out of the east. And because you have already lost $30 hedging on Detroit you now have but $82 to play with on the finals. Say Boston represents the east and San Jose is a -200 series favorite, (Boston is +180). You would need to invest $30 on Boston to win $50.
Bottom line:
If Boston won the cup you would net $10. (Lost $10 on your original bet with San Jose, lost $30 on the Detroit hedge and won $50 on Boston).
If San Jose wins the cup you net $62. (Lost on the $30 Detroit hedge, lost $30 on the Boston hedge, and won $112 on your original San Jose future.)
There are numerous ways to get better odds, ( by using adjusted series prices), but this would entail further risk.
My advice. You got a great price on San Jose at 12/1, sit on it till the last round in the western finals, see who their opponent is and then reassess.