^ Well that turned out to be weirder than I imagined! Thanks.
As I understand it, any regular registed voter can take part, but they have to be sufficiently commited to hang around for sometime in a conference hall and stand in a designated place to be head-counted as supporting one guy or other as a Presidential candidate. Is that right? Do you think a guy can go stand in a Dem caucus one night and then in a GOP caucus the next night? I presume America will also be watching for how many people total turn up at the Dem meetings and how many at the GOP. That's an important indicator too.
EDIT: Thanks for that extra info, and classic Frownland slant !