Alaska just passed automatic voter registration at the ballot box. A ton of other states can, too.

Five states (plus Washington, D.C.) recently passed laws or instituted new procedures to implement automatic voter registration, but when Alaska became the sixth such state last month, it was the first to do so at the ballot box. This success offers an important way forward for progressives, because Republicans have been almost implacably hostile to the concept of registering more voters...
http://www.dailykos.com/stories/1606536