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Those behaviors may have contributed to the collapse of Republican support in Kentucky’s urban areas and more affluent suburbs, such as Campbell County and Kenton County, on the Kentucky side of the Ohio River, across from Cincinnati. Trump carried both in 2016, but this time, surging turnout tipped both counties blue. Thirty percent of adults in Kenton over the age of 25 have college degrees, as do 31.9 percent of those in Campbell County.*

But the true fire bell in the night for Trump and his party comes from a different direction: from the slump in Republican voting in southeastern Kentucky, formerly coal country.

What happened there?

No state saw a more dramatic improvement in its health-care-insurance enrollment under the Affordable Care Act than Kentucky. And no part of Kentucky benefited more than the southeast from the ACA. I wrote here in The Atlantic in 2017:

[Rand] Paul won 76.6 percent of the vote in Clay County, where 15.6 percent of the total population has gained coverage via the ACA’s Medicaid expansion. He won 81.5 percent of the vote in Jackson County, where 15.1 percent owe their Medicaid to the ACA. He won 84 percent in Leslie County, where 18 percent would lose Medicaid if Obamacare were repealed.

As the benefits flowed, Kentuckians—once staunchly opposed to Obamacare—came rather to appreciate the Affordable Care Act. By 2018, a plurality of Kentuckians—44 percent—approved of the ACA. Matt Bevin made it his top priority as governor to shred the ACA in Kentucky. He shifted 31,000 people off Medicaid and S-Chip, the state children’s health-insurance plan. He added work requirements for Medicaid, and other practical barriers to coverage.

Bevin’s personal behavior may have been extreme, but his policy priorities as governor were squarely in the GOP mainstream. Squeezing the ACA has been Trump policy, too. Nationwide, Medicaid and S-Chip enrollment has declined by 1.7 million over the past two years, a decline too big to be explained solely by improvements in the job market.

The central idea of the Trump candidacy and the Trump presidency has been that Trump’s abnormal behavior could win just enough votes from culturally conservative whites to overcome the unpopularity of the Republican agenda. Kentucky tested that proposition—and proved it false.

Read more: When Matt Bevin tried to undo Obamacare

Donald Trump carried Kentucky in 2016 by 30 points, almost 600,000 votes. Twenty-three percent of Kentuckians live in rural areas; more than 40 percent of households own firearms. Trump campaigned in Kentucky 24 hours before the vote, intensely personalizing the contest in a state where he thought himself popular. He claimed that “radical Democrats are going totally insane” and charged that Democrats want to “destroy anyone who holds traditional American values.”