This group has recently uploaded raw footage of a 2006 Arizona townhall meeting where John McCain was asked one or more questions about immigration. The playlist with the videos is here, but I haven't reviewed them for anything of note.

On this video - which is probably part of that collection - he's asked for figures on the numbers of anchor babies that he wants to give amnesty to. McCain then says he refuses to dignify that question with an answer. When someone - presumably Michelle Dallacroce from MAII - objects, one of his assistants and someone from the location's staff threatens to have her ejected.

First, anchor babies are (as far as I know) per definition U.S. citizens. So, they themselves wouldn't be part of McCain's amnesty, although many of their parents certainly would have been. So, the question makes little sense. Second, she was being a bit disruptive so they were within their rights to threaten to have her ejected. If they had done that simply because of the question she was asking during her turn or if it had turned into a taser incident, then we'd have something.

I'll leave it to others to watch the videos and if there's anything useful on them please leave a link and a time when it appears.