ad blitz vs advertising campaign

ad blitz and advertising campaign both are nouns.

Word	Noun	Adjective	Verb	Adverb
ad blitz	Yes	No	No	No
advertising campaign	Yes	No	No	No

As nouns, ad blitz and advertising campaign are synonyms defined as:

ad blitz and advertising campaign: an organized program of advertisements

Other synonyms of ad blitz include ad campaign.

ad blitz (noun)	advertising campaign (noun)
an organized program of advertisements	an organized program of advertisements