Show a different Storyblok promo block to visitors from a specific campaign

Running paid campaigns that land on a Storyblok page and I want the promo block to change for people arriving from one specific compaign. I got as far as this in the audience editor and then got stuck on which fields map to the UTM params:

campaign is "spring-sale" ...?

Which CQL variable is the campaign name, and how do I match source or medium if I want to be more specific?