Supporters of campaign finance reform at a gathering at the U.S. Capitol. (Win Mcnamee/Getty Images)
Opinion writer

It has become a truism that the American political system is suffering from dysfunction. But weirdly, even the insurgent candidates, Donald Trump and Bernie Sanders, don’t talk much about how they would fix it. This is a populist insurgency without a clear manifesto.

So it’s refreshing to hear Rep. John Sarbanes (D-Md.) present a detailed action plan to try to repair what’s broken. This proposal isn’t a cure-all. It wouldn’t fix the immigration problem or fund Social Security or fight terrorism. But by changing the way we fund elections, this proposal could make it easier to elect the politicians who would make the U.S. government work again for its citizens.

Sarbanes presents his proposal in the current issue of the Harvard Journal on Legislation. It’s a simple idea: Congress should free itself from big-money, special-interest domination by encouraging an alternative system of small contributions that would be matched with public funds. This isn’t a new idea — Teddy Roosevelt proposed a version back in 1907 — but it’s a good one, and a way to start curing what ails us.

“The republic is in dire straits,” Sarbanes writes. “The governed perceive the government as corrupt. The vast majority of Americans are convinced that the wealthy and well-connected call the shots in Washington. . . . Americans are increasingly convinced that a plutocracy has taken hold.”

Sarbanes explained in an interview what he sees as the downward spiral of U.S. politics. “The solid citizens are judging that the system isn’t responsive to them. When these folks vacate the political town square, it creates a vacuum — and extremists take over. A second thing happens, too: By leaving, people cede the town square even more to the elites, which drives policy even further away from what people want.”

Members of Congress are caught in this vortex. Unless they’re personally wealthy, they’re perpetually raising money. Campaign spending for House elections increased 610 percent between 1984 and 2012. Sarbanes writes that a House seat cost an average of $1.5 million in 2012, which meant that a candidate had to raise more than $4,000 a day in the off-year to have the necessary stack of cash. No wonder they have no time or inclination for solving problems.

Sarbanes has a twofold answer to this money-driven process of decline. First, he would create a 50 percent tax credit for small campaign donations up to $100 in every two-year election cycle. Second, to amplify the voices of small contributors, he would provide a 6-to-1 match for their donations to qualified candidates. To participate, candidates would have to raise at least $50,000 in small contributions, limit each donor to $1,000 per election and forgo money from private political action committees.

PACs now dominate the political space, thanks to the Supreme Court’s unfortunate refusal to limit secret money in the 2010 Citizens United case. Sarbanes thinks his plan would pass muster even with this court. To help the publicly financed candidates cope with the inevitable surge of PAC money for rivals, he proposes a formula that would allow candidates to tap $500,000 in extra federal matching funds in the last two months of a hot campaign.

Sarbanes argues that for members of Congress, this approach would create a real alternative to a system that many of them detest. It gives power to the little guy: A $50 donation would become $300. A living-room gathering that collects 30 of these $50 donations would raise nearly $10,000.

This system would cost taxpayers hundreds of millions of dollars per election cycle. That won’t be an easy sell for a country that seems to despise politicians. But it’s a fraction of what private interests spend or, say, the cost of what taxpayers spend for one new ballistic-missile submarine. The truth about politics, like everything else, is that we get what we pay for.

The public-funding idea isn’t as unpopular as you might think. A recent poll by Democracy Corps found that 72 percent of respondents favored Sarbanes’s approach.

The United States’ rebellion against the political status quo is the central political fact of 2016. Pretending that it will go away is a mistake. This alienation has been building for a decade, first with the tea party on the right and the Occupy movement on the left, and now in Trump and Sanders. But so far, this deep disaffection has produced mostly negative results — spawning anger and division that will make the system even more dysfunctional.

Angry, alienated Americans need an objective: How about changing the rotten system that has gotten our politics into this paralyzing decay?

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