However when you at the speakers at their conventions...oh my.
David Boren (D-OK) was a guest speaker at either the 2010 or 2011 convention, I forget which. I think the NRA would gladly welcome pro-2A Dems; but the current Dem leadership has created a situation where it is difficult to advance in the party without supporting gun control - and even when they back off for a decade or so, eventually the Dem leadership comes aling and says "Vote for gun control or you will get no funding from us AND face a primary challenger."
Until the Dem leadership is more pro-Second, Dem politicians who genuinely support the Second Amendment are going to be a rare breed - and with the Dem internal party structure, it is going to be very difficult to get the Dem leadership to allow such a thing. Look at Tom Daschle - hosed his own constituents in a rural state rather than cross Dem leadership on gun control and became one of the first sitting Senate Majority leaders in decades to lose an election.