Gitcoin never did an ICO and doesnt have a token. During the 2017 ICO craze, we opted instead to just focus on product/community.
Our network supports any ERC20 token or ETH. Here are the top ones on the Gitcoin network https://gitcoin.co/leaderboard/tokens?cadence=all&keyword=al...
More on why we didnt do an ICO at https://gitcoin.co/not_a_token
The pool of funds is then allocated based on the unique donors each project had.
The math is quite interesting, but unfortunately it assumes identity in order to be implemented in a decentralized setting.
[1] https://vitalik.ca/general/2019/12/07/quadratic.html