As you said why there is the provision to post only one poll at a time. It is because suppose if i want to post 10 polls then their will a huge problem for editor to verify the polls of each and every users. That way there is the provision to post only one poll at a time.
I am not asking the webmasters to increase the polls to 10 instead i was saying only to make it 2. I think so that it can be done.