NY's celeb hotspot of The Hamptons is home to a gift store called The Monogram Shop, and it might've just forecast how Election Day shakes out ... via these branded cups it's hawking. They've got branded cups for Biden and Trump, but apparently, more MAGA types are in town to quench their thirst.

As you can see, the shop owners have been flaunting signs in the window from their latest cup wars ... proving Donald is, uhh ... trumping Joe, so far, anyway.

Of course, this is hardly scientific, but here's the breakdown of the store's figures: On the day Trump got shot last weekend, 142 cups with his name flew off the shelves, both online and in-store. In contrast, Biden’s cups barely hit 52.

Not shocking, really, on the day DT survives an assassination attempt.

But, Trump's cup craze hasn’t let up since -- his items sold out by Wednesday, after clocking in overall at 2,251 cups, while Biden's cups lag behind at 793.

As everyone knows, NY state is a Democratic stronghold, but The Hamptons region of Long Island tends to be split down the middle between Dems and the GOP.

So, the cup game seems to be reflecting some serious political heat, and a surge for Trump, post-assassination attempt ... while Biden's coping with mounting calls for him to bow out of the campaign.