Speaking as a guy with a lot of experience with voter data ( I built the first "where do I vote" apps for Google and helped found the voting information project): This is actually almost entirely public data. Yes, including addresses and phone numbers and political affiliation. There are some states that is not public as part of the voter file, but you can still get it other ways publicly. For example: USPS, etc. Som…
Birthday is an included item. That's definitely private as it is often used to confirm identity.
"almost public" is meaningless. One data item, like credit card number, or birthday, can make this a dangerous leak.