Ye just filed legal docs to lock up the rights to "God Save America" -- which he wants to slap on shirts, sweaters and hoodies in what seems to be a final-ditch effort to push his message that was front-and-center in his 1st campaign ad ... bringing faith back to politics.

Unclear if this is a campaign slogan -- like Barack Obama's famous HOPE or Trump's Make America Great Again -- but it sure reads like one. The phrase also feels like a play on "God Bless America" ... both patriotic, but kinda sanctimonious too with "Save" swapped in.

Kanye filed for the trademark last week, which lines up closely with the release of his debut campaign ad ... something that just hit the ether Monday, 3 weeks before voters hit the polls on Nov. 3. Some people feel this ad -- and maybe now this new catchphrase he wants to lock up -- is too little, too late. That, or maybe just in time ... depends on who you ask.