To the original question - it depends on who's the one pushing for it.
To be sure, there is a particular flavor of anti for which the disarmament thing is part and parcel of a generally socialist utopian ideology, basically "well if no one had weapons, no one would kill anybody" - you know, the crunchy granola or "New Man/New Society" types.
I think most of those actively pushing the disarmament agenda on the left are like that, with the comparatively rare exception of the big ones - Kennedy, Schumer, Feinstein - those few I think are at best elitist "power for me and not for thee" wannabe nobles, and at worst are of the "we have to disarm them before we can do more they wont like" thought pattern. But that's a definate small minority.
With the exception of (comparatively rare I think) true believers, many seem to just line up depending on what the platform is - "I'm an elephant, so I'll vote (sorta) RKBA. I'm a donkey, I won't" It's just not a big issue to most folk.
As to us just folks, what seems the most common "anti" all over the political spectrum is just folk who haven't really thought about it at all - that can range from "ooh, a gun in the house means you're more likely to die, those are icky" to "well yeah I have a .38 and a hunting rifle, but who really needs an assault weapon. Those are criminal guns, I saw it on TV." And those are if not as likely to vote R as D, at least present in both parties. They're also the most reachable, as they don't have the vested interest the others do. And pragmatic arguments trump Constitutional ones most all the time.
And finally yeah.. there's exceptions to every generalization.
