Is there a way to copy a message that's in one email campaign to a different campaign?
Currently it is not possible to reassign an email message from one campaign to another. An alternative option is to copy the HTML content from the email to a text editor, create the new email under the correct campaign, and paste in the HTML content from the text editor.
Another solution is to copy the email campaign. In doing so, all the messages will be carried over and you can simply re-name the campaign.