A dense cloud of abject nonsense and alleged corruption is emanating from the White House. But you can cut through it with four words: It Only Takes 20.

Or, if you like, #itonlytakes20.

Twenty votes in the Senate separate the drive to impeach the 45th president — which is now supported by about half of voters — from the conviction that Donald Trump’s conduct in the Ukraine matter and elsewhere merits.

The Midwest is hurting

Here’s the thing: The votes likely must come from states where Trump’s polls are cracking, and where new research from Deutsche Bank, the president’s lender of choice, says his policies have stopped helping local economies.

The economy is stalling in the Midwest, where Donald Trump broke through a purported “blue wall” to win the presidency in 2016.

“There is significant overlap between manufacturing activity at the county level and the 2016 electoral map, suggesting that more manufacturing-intensive counties, which have shouldered the brunt of the trade war, also skewed towards supporting Republicans,” Deutsche economists Justin Weidner, Matthew Luzzetti and Brett Ryan write.

See:This map shows how the trade war with China is hitting ‘Trump country’

“To the extent that the manufacturing slowdown continues unabated, which is likely unless there is a de-escalation in trade tensions, the electoral map could be more difficult for President Trump and Republicans in 2020,” the Deutsche economists conclude.

Tuesday was bizarre, even by recent standards.

Flunking constitutional history

Justice Department lawyers trying to keep Congress from seeing special counsel Robert Mueller’s files from grand-jury proceedings basically got laughed at by a federal judge. White House Counsel Pat Cipollone informed Congress that the administration won’t comply with subpoenas in the impeachment inquiry, flunking constitutional literacy in his letter to Nancy Pelosi.

By evening, emboldened by Trump’s decision to pull U.S. troops from their peacekeeping and mop-up roles in Syria after dispossessing Islamic State of its caliphate, Turkey was preparing to invade.

And Trump threatened to sue the city of Minneapolis, claiming his campaign was being overcharged for security at a rally scheduled for Wednesday night.

But what abides — as NBC News and the Wall Street Journal released a poll showing 55% of Americans approve of the impeachment inquiry, and 43% think Trump should be removed from office — is that it would only take 20 Republican senators’ votes out of 53 to end this mess, presuming Democrats in the chamber vote as a bloc.

Whip count

It’ll be hard to get those votes, but maybe it’s getting less so. Consider polling and economic data while bearing in mind former Arizona Sen. Jeff Flake’s comment that 35 Republican senators would probably convict Trump in a secret ballot.

Begin with swing-state senators up for re-election in 2020. These include Maine’s Susan Collins, Colorado’s Cory Gardner, Arizona’s Martha McSally, North Carolina’s Thom Tillis, Montana’s Steve Daines and Iowa’s Joni Ernst. Throw in some from safer states who often criticize Trump, including Nebraska’s Ben Sasse (also up for re-election), Utah’s Mitt Romney and Alaska’s Lisa Murkowski.

Then there are retirees. Pat Roberts of Kansas is leaving Congress, as his state trends away from traditional GOP loyalties. Then there’s Tennessee’s Lamar Alexander, a 79-year-old former protégé of Senate GOP Leader Howard Baker, who helped force Richard Nixon from the presidency after Watergate. They’ve got nothing to lose from bucking Trump.

That’s 11 — and counting?

Manufacturing recession

Then consider senators from industrial states where Trump’s trade policies are hurting growth, or so Deutsche Bank says — which removes one incentive senators might have to look away.

Indeed, Deutsche estimates trade-policy uncertainty will shave a full percentage point off economic growth nationally in early 2020 — calling the coincidence of a slowdown and trade tensions “undeniable.” Counties with high manufacturing exposure have seen slower job growth and wage growth than less industrialized areas — with the trade war reversing more positive trends that had emerged by 2017, the economists add.

Job openings plunged 11% in August and are down 15.6% in the past year in the Midwest states, according to the latest figures from the Bureau of Labor Statistics.

This is where you begin thinking about Pennsylvania’s Pat Toomey and Ohio’s Rob Portman. In a rigorous world, South Carolina’s Tim Scott would be wobbly — his state’s top five employers include Boeing BA, +6.83% and BMW BMW, -2.60% , crucially dependent on trade, and it’s 27% African American, as is Scott himself.

That’s 14. It’s enough to start the count, at least.

Polling numbers, state by state, should embolden senators to think impeachment is not politically perilous. The president’s long-stable ratings are cracking.

Support cracking in red states

In Arizona, Trump’s net approval rating has slipped six points since last October, to negative 4 from plus 2, in Morning Consult polling. In North Carolina, there’s been a six-point dip to negative 3. In Montana, a whopping 13 points to negative 3. He’s down six in Ohio, to negative 5. Down five in Florida to negative 2. He’s even down four in Kansas, to plus 4, in a state Trump won by 20 points. He’s also lost ground, weakening already-negative numbers, in Pennsylvania, Iowa and Wisconsin — which all have above-average manufacturing exposure.

Conventional wisdom on Republican resistance to impeachment has had two prongs. One is that senators fear facing primary challengers backed by Trump’s base. The other is that voters saw Trump fighting the fight for blue-collar workers — and that he was good for the stock market, though the Standard & Poor’s 500 SPX, +1.59% and Dow Jones Industrials DJIA, +1.33% are little changed from early 2018.

Both arguments are collapsing.

A credible 2020 Senate challenger needed to begin raising money a year ago. Portman and Toomey, who face voters in 2022, know Trump will be — at best — a lame duck by then. Meanwhile, Deutsche Bank dismantles the economic case for Trump as man of the people.

Tuesday’s craziest headline was the line in a Senate Intelligence Committee report saying that Russian spies toasted Trump’s 2016 win on Election Night, boasting that they, the Russians, had made America great again.

See:Russian election-interference efforts have only increased since 2016: bipartisan Senate report

What an impeachment really would take is 20 senators from the president’s party who believe their own platitudes about the Constitution and the rule of law.

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