Hi juniordev,
I assume you're talking about the Popular & Recent Content on the hope page of thwack. You can see that some of the polls are created in the User Polls group, while others, depending on their content, are created in specific product forums.
What you see on the home page is actually an overview of the recent and most popular content, based on the activity of each thread. So this is a matter of what and when users post, whether it's a poll or an idea or a discussion.
Kind regards,
Maria