I've been following the immigration threads for quite awhile; never have I seen anyone post they are against LEGAL immigration. What they are against is lawbreaking to get in, and the encouragement of lawbreaking (i.e., amnesty) to get in.
Here are a dozen posters who want to stop LEGAL immigration too - and that's just one ONE thread: http://www.freerepublic.com/focus/f-chat/1608492/posts