Oh, but I have seen that argument presented here. I remember several threads where GOP loyalists complained that the NRA was endorsing a pro-gun Democrat over their candidate. They never could explain why the NRA should sell out gun owners over non-RKBA causes.
Don't get me wrong, though. While the Dems in the house are pulling their AWB II out of the archive right now and dusting it off, Republicans like King are going to be right there with them to (hopefully not) get it thru.
And you know what else? Don't be surprised if it turns out that the NRA (quietly, for the sake of compromise, mind you) looks the other way while they pull everyone in on it together, deciding who's gonna vote for it and who gets a pass. (Example: Dan Boren, Oklahoma 2nd District congresscritter and NRA Board Member.)
If it makes it thru the house, Reid will get it thru the Senate because 0bama will tell him to and we'll have another "assault weapon ban" - again, because they'll be looking for enough weasel Republicans like Snowe, Collins, et al to vote for cloture.
Then the NRA will have more marketing material and can raise more megabucks. Just as 0bama has been the best thing ever for firearms sales, a new gun control bill becoming law would be the best thing ever for the NRA. Better yet that if it succeeds it will be done by liberal Democrats and RINO Republicans. Thus they all really kinda work together to scratch each other's back - except now we're dealing with real Marxists who are also gonna mess with the internet, news outlets that give the opposition fair time and free speech in general. The stakes are high and people seem not to know it or to not care.
But the best chance of stopping it is in the house where frankly most (maybe not all) of the pro-gun votes that can be counted on are Republicans, and most (maybe not all) of the pro-gun votes that can't be counted on (IOW the Weatherby over-under pheasant gun types who will vote the way Nancy tells them to) are Democrats.