Yeah, but aren't they always doing that?

Well, they probably feel they stand a lot better chance now that gay marraiges are being seriously considered. I'd actuallly be interested to hear what the arguments against polyagmy are from those who support gay marriage (that is, if those who support gay marraige are actually opposed to polygamy). Not that the two are really related, but if the argument for gay marriage is that people should be free to marry whomever they please, regardless of gender, should society stand in the way of multiple people getting married if it makes them happy?