In order to clone an existing campaign, simply click on the mark located to the left of the campaign name.
A list of options will appear. One of them is the option to clone the campaign.
By selecting to clone the campaign, a new campaign setup page will open and you will be able to edit any of the existing setups.
This is a good option if you want to create the same campaign for different Geos.
Please note that you can only clone a specific campaign and not a campaign group.