I believe you need to leave that chunk of code in your script that you removed.
Your problem is that you are including class_poll.php more than once in your code somewhere. Find where that is and remove one of them. If that doesn't work, put in back in and remove the other one. If that still doesn't work, or you're getting a different error message, let us know.
FWIW, I do have on my "to-do" list for the weekend of looking at your .txt versions of your scripts. I just spent this evening testing phpdig 1.8.3 with all my customized code. It's looking good!