Apparently there is a problem when executing functions with .delay. Temporarily, the upload of voters will not be executed in the background.
(Removed .delay from the call to tasks.voter_file_process in views.voters_upload.)
Emails sent to voters with credentials for voting now includes voter group.
Corrected email port in settings.py to 25.
All tasks called with '.delay' (using celery) that were previously commented are now back to using '.delay'.
Thus, celery deamon must be running in order to these tasks to complete. Otherwise, they keep as "not yet processed".