Throughout the gift collection period, you'll receive periodic email reminders to help you monitor the amount contributed.
If you have a concern about a shortfall for the gift goal, you can always invite more friends to contribute! It's easy to send reminders to friends you already invited -- and it's also a breeze to invite others for the first time.
You can also extend the delivery date to give others more time to contribute.
All of this can be done from the Group Gift Management screen -- a link to this screen is included in each email reminder.