The answer, according to the National Conference of State Legislatures, is 25 in some form.
The group’s website has an interesting breakdown of the different types of public campaign financing and which states participate in which programs. They break it down into three groups: Public funds given directly to candidates, income tax check-offs that are delivered to political parties and tax incentives for citizens who donate to a campaign.
Fourteen states fall into the first category, and advocates for public campaign financing in New York want the state to become No. 15.
Ten states have some sort of income tax check-off or add-on system, which directs a few dollars to a specific political party if a citizen checks a box on their tax return.
Seven states have a tax write-off for political donations. Of those states, most offer a total write-off of $50 or $100 each year.
You can click the above chart for a more detailed breakdown.
And be sure to check out our look at the battle over campaign finance reform in New York, where Democrats are pushing for a public option while Republicans are in opposition.