There might be some common generalized distrust of Catholics in areas where they are uncommon (basically the South), but going out on a limb to call the Catholic Church the whore of Babylon and having a whole eschatological premise for it is more-or-less beyond the pale.

The point is, though, that a significant portion of the Catholic community votes quite socially conservatively, which tends to mean Republican. If the Republican candidate then starts promoting his connection to a person with a rabid hatred of the Catholic Church (which he has done -- it's not just an unrequested endorsement; McCain allegedly sought the endorsement and has emphasized it in speeches) shouldn't the Catholic community be made aware of that? Especially when Obama was publicly pressed into disavowing the unrequested endorsement of him by Louis Farrakhan?