So is this kinda data-collection on voters legal in the US? the whole speculation on religion and so on?
In regards to collection, yeah, probably.
The data leak contains a wealth of personal information on roughly 61 percent of the US population. Along with home addresses, birthdates, and phone numbers...
This part is standard in every voter registration file I've ever seen. Phone numbers weren't usually required and tended to be pretty spotty at best. But yeah, all of this info is collected when you register to vote and the election agencies do make this available to campaigns. This helps keep campaign costs down because campaigns can target their efforts towards people they want.
...the records include advanced sentiment analyses used by political groups to predict where individual voters fall on hot-button issues such as gun ownership, stem cell research, and the right to abortion, as well as suspected religious affiliation and ethnicity.
I'm not sure what would be illegal about this, it's just basic market analytics of bouncing data off one another.
Take the voter registration file and bounce it against a list from a special interest group that you have. Boom, now you can target by district and membership in that special interest.
Or bounce it against another publicly available list. The Iowa GOP made gains in the early 90's by bouncing the voter file against vehicle registrations because the Democrats had made a change in minivan registration that hurt families.
Or bounce it against data you generate yourself. I've seen mass surveys that polled how a voter stood on 15-20 issues, which was then bounced against the voter file and used to target mail and other campaign efforts.
Or, be like Google/Amazon and use the available information you do have to make inferences/assumptions/speculation about a person.
I can understand private companies doing tons of data gathering, cross referencing and general Big data processing.
But the fact the political parties are aware of this, finance and have access to it without breaking any law, is interesting. I mean, this is straight up individual profiling.
So? There are profiling you, they want to know whether you're likely to vote for them. If you are, they're going to do everything they can to make sure you vote. If not... well, if they start acting on that, that's when you start investigations.