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But we know the flip side as well. When the American people think the economy’s headed in the wrong direction, they’re liable to punish the president’s allies across the country. That’s what happened in 1982, 1994, and 2006. And that’s why it’s so remarkable that Republicans are struggling one week out from this year’s midterm.

If a political pundit arrived on the scene today not knowing anything about the past two years in politics, she’d likely look at the economic indicators and presume that the GOP was flying high. But President Trump’s divisive social agenda and pugnacious personality are so unpopular that he’s dragging his entire party down with him. Republicans are hemorrhaging mea culpa voters who regret having voted for Trump in the first place. And that will cost the GOP not just in House races, but also in state houses across the country.

What’s a wave election? It’s a force within the electorate that proves more powerful than the structural impediments it overwhelms. The barriers to Democratic success are formidable, including voter suppression, gerrymandering, and a 3.7 percent unemployment rate. But Democrats are seeing their support swell high enough that it’s likely to overtop those barriers, not because of the economy but in spite of it.

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No Democrat needs to be reminded why statewide elections in places like Pennsylvania, Michigan, and Wisconsin matter in presidential campaigns. But until now, the DNC has seemed intent on letting everyone ignore the GOP’s biggest vulnerability, namely the fact that those three states—not to mention swing states like Florida, Ohio, Iowa, and Minnesota—are electing governors next week. If Democrats end up flipping state houses in places Trump won in 2016, they will have proved themselves capable of winning in the places coastal elites derisively refer to as “flyover America.” You can’t overstate how big a deal that will be.

It’s not that power in Congress isn’t important—it is. But over the long haul, the gubernatorial contests are likely to have a much bigger impact for three reasons. First, swing-state Democratic governors will have road-tested the messages best equipped to sway voters in the most important swing states. Nothing could be more valuable for our 2020 nominee.

Second, across most of the country, state officials will soon be tasked with redrawing the nation’s congressional districts. A decade ago, Republican governors helped the GOP gerrymander itself a decade’s worth of political advantage in Washington. If Democrats do well this year and again in 2020, they’ll be poised to flip that advantage back on the GOP through 2030.

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Finally, in close presidential elections, a state’s political apparatus can have an outsize impact. Who knows how the 2016 campaign would have turned out if Democratic governors had controlled Michigan and Wisconsin, places where Hillary Clinton lost by three-tenths and seven-tenths of a point, respectively? Our country might be in a very different place today.