Change Apple ID from gmail to iCloud.com
I'd like to change my Apple ID from the gmail.com I'm currently using to an iCloud.com mail address that is currently one of my "Alias" email addresses. I want to get away from using @gmail.com as an Apple ID.
Is it possible to use the current Alias email address as my new Apple ID and delete/stop using the gmail.com address?
If not, what can I do to make it happen?