Neither. It will be used as a political crowbar, most emotive issues are, the Republicans have already started to use it as an excuse to bash Obama's stance on immigration etc. I also, (given the sheer number of these tragedies that have already occurred, and the relative lack of movement on the gun control issue), believe that the pro-gun crowd, specifically politicians and lobbyists, are unlikely to change their stance for anything less than a similar tragedy which directly impacts on them or their families.
The 51% example was probably heavy handed but I stand by the general ideas.