The Democratic Party came rather close to a staggering upset on Tuesday night in a special election for a House of Representatives seat in Kansas. The vote was to replace Mike Pompeo, who was tapped by President Trump to run the CIA. The seat went to Pompeo by 31 points in November, but pro-choice Sanders Democrat James Thompson managed to hold Republican state treasurer Ron Estes to 7 points — despite the fact that Thompson got almost no help from the national Democratic Party, while Estes got a ton of money and personal assistance from Ted Cruz and Trump, among others. It was a remarkable performance.

This surely is a good omen for Democrats — though a loss is a loss, and it's not clear this will generalize to the 2018 election. But I think it's safe to conclude this is bad for Republicans, no matter how you slice it.

Though there has been no polling specific to this district, and little detailed attention from journalists, it seems some combination of two factors were behind this result. First, the infighting, chaos, incompetence, and horrendous policy proposals of the national Republican Party and the Trump administration have massively energized liberals and leftists across the country. Democrats have lately had poor turnout during midterm and off-year elections — getting this close during a one-off special election is a huge break from that trend.

Second, Kansas Republicans have very badly harmed their constituents with garbage conservative policy. Gov. Sam Brownback and state legislators turned Kansas into a testing ground for utopian Heritage Foundation notions about massive rich-tilted tax cuts unleashing economic growth. The results were precisely the opposite: growth, new jobs, and new business creation weaker than the national average, and a gigantic budget hole that required vicious — and horribly unpopular — cuts to basic services.

The weak growth is almost certainly a direct result of the tax and service cuts. Such policy directly increases inequality, which is a structural drag on economic output due to rich people spending less of their incomes than poor ones. Meanwhile, as economist Marshall Steinbaum argues, taxes can serve as a sort of diversionary force pushing money out into the broader economy. If top marginal tax rates are high, there is more incentive for corporations to spend on workers, research, and investment — but if they are low, there is more incentive for executives and shareholders to strip the wealth out of the corporation as fast as possible.

In the 1980s, there was enough of the New Deal tax and income structure remaining that it could be devoured by the rich without causing immediate disaster. But that is virtually all gone now, and inequality is back to pre-Great Depression levels. As Brownback, Louisiana's Bobby Jindal, and George W. Bush have demonstrated, conservative economic policy does the exact opposite of how it is sold. Even Kansas Republicans are blearily beginning to realize this, as they recently attempted to accept ObamaCare's Medicaid expansion — though Brownback vetoed it, of course.

Comprehensive Republican failure has created a political opening for somebody. But it's not clear that the extant Democratic Party will be able to seize the moment. They barely helped Thompson at all, and local elites tried to run a traditional Blue Dog conservative-lite candidate who almost certainly would have lost by a wider margin.

However, lack of help from the Democratic elite in itself may be for the best. As Matthew Stoller argues, the Democratic Congressional Campaign Committee (source of the most obnoxious fundraising emails in politics) often seems far more concerned with preserving the power of the current Democratic leadership and getting the right sort of Democrats elected — ones comfortable with Wall Street and corporate lobbyists, that is — rather than winning elections per se.

At any rate, Thompson's near-miss is very convincing evidence of the potential of Sanders-style politics in rural, red-tilted districts. These days, rich-friendly conservative-lite Democrats will almost always lose to rich-worshipping, conservative-heavy Republicans. But genuine left-wing populists can inspire fervent enthusiasm from the Democratic base — thus solving the turnout problem — and make up most of the rest of the distance by credibly attacking conservative policy. That is a key difference from Blue Dogs, who support the same economic policy as Republicans, just somewhat less of it. Indeed, it very well could be easier to win without the meddling consultant class from the DCCC. And organizations like ActBlue, Daily Kos, and Our Revolution can step into the breach with fundraising, phone banking, and voter outreach, as they did for Thompson.

So lefties in West Virginia, Alabama, Louisiana, and elsewhere, take note — match Thompson's mark across the country, and Republicans will lose 122 House seats in 2018.