They also once supported Dingy Harry, too. Not to mention the NRA coined the phrase “Sporting purposes of firearms”, and were behind every major gun control bill including the 1934 National Firearms Act and the 1968 Gun Control Act.
Check out their March 1968 American Rifleman where they brag about it.
And Dingy Harry repaid them by killing Obama’s new AWB and background check bills even though Newtown was still fresh in everyon’s minds. It’s almost always useful to have the senate majority leader beholden to you.