Yes! I've written one. It's called ENOF. It's not quite that, but in that direction. It starts as a real-world quest game in SF and slowly becomes the government. Instead of an AI voting as you, everyone names a person whose judgment they'd accept, and those delegations chain together into what people start calling the respect graph. You can revoke yours instantly, and a lot of the book is about what goes wrong anyway: bought delegations, one schoolteacher in Lagos ending up with eleven million votes behind her, and eventually who gets the authority to turn the whole thing off.
First 100 HN readers can get it free (DRM-free EPUB/PDF): https://solyin.gumroad.com/l/enof/HN
Seconding Franchise, though. Asimov got to the "one voter stands in for everyone" version in 1955.