Once a user submits their answer to a poll question within a post, it seems like there is a missing </div> tag at the end of the gpoll_ajax_container div class.
All the content of the post ends up getting wrapped into the gpoll_ajax_container div and our sidebar gets moved to the end of the page. The post isn't published yet so I don't have a link, but I can figure something out to have you look at it if need be.
I only observe this behavior when an answer is submitted to a poll placed in a post. The sidebar widget does not have a problem and there is no issue when you just click to view results.