Safe-guarding your personal identity information is crucial. Online transmission is not always secure.
Simply put, the open Internet is not secure, therefore it is not secure to email your voter registration request form. Unless you have some special type of secure email or file transfer mechanism, you can consider your regular email as not secure. It is especially hard to control the level of security over the Internet traveling through many countries around the globe. Messages and attachments can be found and changed without your knowledge.
PDF files are not secure documents unless they go through a secure file transfer system. Don't let your personal identity get stolen by sending an emailed attachment through regular email. You will find, with voting, it is usually possible to use the post for transfer of registration and ballot documents.
Unless your election office offers a secure (encrypted or password protected) manner of emailing your application to them, we highly suggest that you rely on regular post and/or Fax. Keep in mind, your entire identity is on the federal registration/ballot request form and it is information that should remain closely held.
To find your election office’s mailing and fax information, please see the Election Official Directory. Once there you can input your state and region, and then click on the “Address Information” tab or “Election Official Contact Details” tab for more information.