The Democratic candidates for president are trying to outdo one another with their ambitious proposals to reform the campaign-finance system. Yet without one vital change, none of these plans will make any difference.

One candidate, the Harvard professor Lawrence Lessig, says that if elected, he will resign as soon as his reforms are enacted, all but guaranteeing he would serve a full term. Hillary Clinton, Bernie Sanders and Martin O’Malley all want to stay in office long enough to appoint Supreme Court justices who will overturn the Citizens United decision, which made it easier for corporations to spend money on political campaigns.

Earlier this week, Clinton called for a constitutional amendment overturning Supreme Court rulings that campaign spending is a form of protected political speech. She also wants to institute a program that matches small campaign contributions with public funds. So do Lessig, Sanders and O’Malley, who is calling for a 6-to-1 match: six public dollars for every private dollar raised, up to a limit.

But a constitutional amendment would be meaningless, and a matching funds program disastrous, if the next president doesn’t first fix the Federal Elections Commission.

No agency better represents Washington’s dysfunction than the FEC. The commission is evenly divided between Democrats and Republicans, and it is hopelessly and endlessly deadlocked. Candidates, parties and independent groups have stretched the law with virtual impunity, but as the amount of money spent on campaigns has increased, the agency’s impotence has become all the more embarrassing.

The FEC, as it is currently structured, is not capable of enforcing existing campaign regulations, never mind more restrictive rules made by possible by a constitutional amendment. Even more troubling is the prospect of the FEC overseeing a publicly funded matching program that would be subject to fraud and abuse.

New York City has a 6-1 matching program for municipal offices, but the presidential candidates are ignoring the main reason this initiative generally has been considered a success: It’s overseen by a nonpartisan board that hasn’t hesitated to fine candidates in both parties who break the law.

If history is any guide, the next Congress is not likely to pass a public financing law or a constitutional amendment limiting private spending, no matter which party is in control. Nor is it likely to create a strictly nonpartisan enforcement agency. But before offering pie in the sky ideas — or announcing “a referendum candidacy” — candidates might try a simpler solution: Fix the FEC first.

— Bloomberg News