You can place all donors from a Donation Campaign into a particular Group through a Query or through the Donation Campaign settings:
  • Through a Query
    1. Select Data Management > Query
    2. Create a New Query
    3. Click Add an Interaction Clause
    4. Select Referenced Types > Donation > Desired Donation Campaign
    5. Click Save
    6. Click Save Query and Run Query
    7. Create a Group from the Query Results
  • Through the Donation Campaign settings
    1. Select Fundraising > Donation Management
    2. Click Edit next to the Donation Campaign
    3. Click '3.Specify Groups and Notifications'
    4. Select the group for under '1. Campaign Group'