I'm reminded of the "Time 100" online poll that Time Magazine held some years back, which a group from 4chan gamed to such a degree of specificity that they not only made moot the winner, they arranged the top 21 winners to make an acrostic.

https://techcrunch.com/2009/04/27/time-magazine-throws-up-its-hands-as-it-gets-pwned-by-4chan/

If you put a poll online, even a totally meaningless popularity contest, people are gonna take that as a challenge. All the more so if the poll actually has some tangible impact on something.