Most readers here probably subscribe to Rick Hasen’s Election Law listserv.
Another good news feed that I rely on comes from Project Vote. You can sign up for their daily (mainly a few times a week) news feed here: http://www.projectvote.org/ (click on the “subscribe to our newsletter” link on the left hand side). I notice that they also advertise a “Voting Matters” blog but sadly I see no mention of an RSS or email feed like Hasen has implemented.