Public financing programs vary widely. Presidential candidates have had access to optional matching funds since 1976, though most major-party candidates now decline them. New York City's 8-to-1 small-donor match is widely cited as a model. Seattle issues "democracy vouchers" — $100 in publicly-funded vouchers each registered voter can give to qualifying candidates.
Proposals at the federal level include the For the People Act's 6-to-1 small-donor match, fully public-financed congressional campaigns, and democracy-voucher pilots.
Defenders argue public financing reduces dependence on wealthy donors and broadens the candidate pool. Critics argue it's a subsidy for fringe candidates and unconstitutional compelled speech.