Ok. Here’s something. I run Apache w/SSL and I always connect to my server over https. Well, it appears that if the siteurl is an https link, it won’t let me in. I switched back to using standard http to connect to my server (I run apache on a non-standard port, so I have to specify the port), it allows me in with no problems.
After logging in as admin, I modified the siteurl values in the options page to reflect the https url, and guess what? I can no longer log in. So, there seems to be an issue with WP not being SSL friendly??