With an initial target of $1,100,000, the game's funding drive closed at $3,986,929 pledged by 73,986 users of the crowdfunding site.
Double Fine Adventure previously held the record, having raised $3.33 million by the end of its pledge period.
"Project Eternity aims to recapture the magic, imagination, depth, and nostalgia of classic RPG's that we enjoyed making - and playing," Obsidian says on the game's Kickstarter page.
"Project Eternity will take the central hero, memorable companions and the epic exploration of Baldur's Gate, add in the fun, intense combat and dungeon diving of Icewind Dale, and tie it all together with the emotional writing and mature thematic exploration of Planescape: Torment."
From October 30, Kickstarter will allow UK inventors and entrepreneurs to submit their proposals on the crowdfunding site.