OK! so here’s the old URL format:
https://boards.straightdope.com/sdmb/showthread.php?t=<id>
The best we can do at the moment is to generate a list of all topics with the word “Poll” in the topic title. That doesn’t necessarily mean there was a poll in the topic though. Here’s one that seems to have been a vBulletin poll: topic id 442232?
https://boards.straightdope.com/sdmb/showthread.php?t=442232
… which redirects to …
Looking at that URL in the wayback machine…
Yay, there is one 2018 crawl! Woohoo! This is why I (and you, if you can afford it) should have a monthly donation set up to the Internet Archive. 
But unfortunately I don’t see a poll anywhere in that archived page? 
If others would like to assist, here’s a Google Sheet with a list of all Straight Dope vBulletin thread ids that have the word “Poll” in the title. I ordered them by id so you can get a rough idea of time by the id; earlier topics have smaller id numbers.
edit: we’re revising the sheet to better match just the word “poll”, so it’ll be less than ~3,500.