This can be done by first going to Reports/View by Campaign and following these steps:

Step 1. Select the campaign you wish to resend.

Step 2. Scroll down to the Opens section and then select Resend to Non-Opens

Step 3. A pop up window will appear where you can rename the campaign (recommended for reporting purposes).

Step 4. Hit Resend to Non Opens and the campaign will automatically be resent only to those who did not open the campaign the first time. Note: Hard bounces will not be processed as they have already been removed.