The API does not have specific clone functionality. However, you could approximate this functionality by issuing a
CampaignService.get with all relevant fields in the
Selector, changing the name of the returned object, and then passing it back into a
CampaignService.mutate call with
operator = ADD. This would only make a "shallow" copy of the campaign, however. You would have to repeat this process using other services if you also wanted to clone objects related to the template campaign, such as ad groups or negative keyword criteria.