If you have a Dynamic User Group and want to use it in an election, you will need to firstly change it into a custom user group.
This is extremely simple, just follow these two steps:
Step 1: Find your Dynamic User Group
Find the dynamic usergroup in question in Admin>UserGroups>Custom>Index
Then click the cog and click 'Copy':
Step 2: Save as a custom user group and include in Auto Refresh
Then in the pop up window, make sure you check 'Save as custom user group' and 'Include in Auto Refresh' (This will make sure it is always up to date with what is in the dynamic usergroup).
You will then be able to select that custom user group in your election!
If you have any further questions, please let us know.