I was confronted with this issue when I lost focus in one of my blogs because of the pressures of work, but felt that somebody else might want to continue what I started. Fortunately, a friend was only too willing to pick up where I left off, thus saving the many precious hours I spent developing that particular blog. The solution is simple enough: move the blog you want to give up, from your account/username to your successor's account/username.
The solution is the same if the scenario is a little bit different. Like for instance, you have several blogs which you created under different usernames. It's so confusing to recall so many usernames and passwords so you'd want now to consolidate these blogs under just one username. This is how to do it:
1. Login to the blog whose username you want to change.
2. Go to the "Settings" >> "Permissions" tab, then click on the "Add Authors" button.
3. Enter the email address of the person or account you'd like the blog to be transferred to, then click "Invite."
4. The invitee or recipient of the invitation (which could be another person or you yourself) should open his email Inbox, open the email invitation, then click on the link provided, in order to join the blog.
5. After clicking the invitation link, a dialogue box will appear. The recipient should "accept" membership by filling up the dialogue box with his pertinent email address/username and password.
6. Login again to the blog whose username you want to change.
7. Go to the "Dashboard" >> "Settings" >> "Permissions" tab.
8. Click "Grant admin privileges" to the new email address/username which was added under "Blog Authors".
9. Click "Remove" for the old email address/username that you want replaced.
From here on, the blog can only be accessed using the new username and password.
