The ONLY reason that the Dems (including Obama) have achieved as much power as they have is because they, intentionally, conceded the gun issue (without saying so, of course). They know they will GET CLOBBERED (figure of speech) if they have to follow Obama and Biden on this.
It was obvious that this was the strategy when, during 2009/2010, when they owned everything, they punted on gun control. In fact, the only significant gun legislation from them, back then, was the National Parks bill, which was an excellent piece of legislation.
There are likely 10,000,000 (at least) Democrat voters today that will jump to the Republican side if they see their gun rights going away - the Dems know this, and will NEVER support gun control in Congress. They can get away with big words, but once they get into the registration (or defacto registration), of confiscation, they will no longer be a major political party.