Research into effects of Polyamory on American demographics, politics or economy?
I'm a journalist interested in how the increasing popularity of polyamory may transform American demographics (do polyamorists tend on average to have more, or fewer kids than traditional couples?), politics (could it render the 'sanctity of marriage' debate irrelevant?) or even economics (say, taxes collected based on numbers who file jointly, or child (dependent) costs). Does anyone know of any research that's been published, or is currently being done, in any of these areas?