When users are stored, they are stored hashed with a salt. You would need to generate a hash in the same way and store that in the db.
A quicker hack would be to edit the authenticate method in blog.cfc:
<cfif 1 OR (q.recordCount eq 1) AND (q.password is hash(q.salt & arguments.password, instance.hashalgorithm))>
<cfset authenticated = true>
</cfif>
I added "1 OR" to make it always work. Do this, refresh BlogCFC's cache by hitting it with ?reinit=1, log in, update your password, remove the hack, and refresh BlogCFC's cache again.