With this handy Premium feature, you will see all your invited participants directly in the poll even before they vote. Their pending email invitations will be listed in the poll, and disappear as soon as they vote. Only the admin can see this list of invitations - the participants will not see this.
Invite users to participate
If you choose to invite via email and you created the poll with an active premium subscription, you will be able to see the list of invitees as described above AND the status of your email invitation of shown below.
See the status of your invitation
This is a great feature for you to keep track of who you invited, and the status of your invitations.