You are wasting your time just deleting his enteries.
A hacker, once he accesses your site will make sure he always has a "back door" that will let him back in whenever he wants - you can delete entries till the cows come home, but unless you clean out the access code he will always be able to get back in - he owns your site now.
Only way (other than by examining every line of code in every programme file) to get rid of him is as follows:
1) Delete entire site from server - ask Host to wipe your hosting account clean.
2) Restore a KNOWN GOOD backup of your site - if you dont have one then ask your host, this must be from before a time when he first accessed your site.
3) Carry out a virus scan of your computer - specifically for "Key Loggers" that record everything you type (that includes passwords etc)
4) Change all you passwords - for everything.
5) If your Blog is "open source" software then look on the tech forums for how to plug any known security holes.
Without carrying out the above yo will never be rid of him!
Good Luck