Democratic Presidential candidate Hillary Clinton Hillary Rodham Clinton speaks at the Inaugural Barbara Jordan Gold Medallion at Texas Southern University on June 4, 2015 in Houston, Texas. (Thomas Shea/Getty Images)

Rep. Sean Duffy, a Wisconsin Republican who was a reality TV star before entering politics, is unlikely to be listed in any Smartest Member of Congress rankings. Yet even he finds it easy to uncover scandal at the Clinton Foundation.

At a House hearing this week, Duffy was in high dudgeon, discussing ties between Hillary Clinton and Boeing. “In ’09, Secretary Clinton . . . makes a shameless pitch in Russia that a Russian airline should buy Boeing airplanes,” he said. “I would like all airlines to buy our great American jets, but she’s making a pitch as the secretary of state! And then, um, in 2010, a short while later, actually Boeing gets the contract for $3.7 billion. And after that, it’s amazing: Boeing makes a $900 million contribution to the Clinton Foundation!”

At this point, Duffy’s neighbor, Rep. Bill Huizenga (R-Mich.) quietly told him the contribution was $900,000, not $900 million.

“Thank you, Bill,” Duffy said, without correcting the record.

Million, thousand — whatever. It’s hard to know what’s more clownish: Duffy’s belief that the secretary of state shouldn’t tout U.S. goods abroad, or that a $900,000 charitable contribution from Boeing (one of about 150,000 donors contributing about $2 billion to the foundation) amounts to scandal.

But Duffy is right about one thing: There doesn’t have to be smoke to give the appearance of fire at the Clinton Foundation. The sprawling charity has sucked in so much cash from so many sources that, with some creativity, it can be tied to virtually any skulduggery.

Alleged wrongdoing at FIFA? There’s a Clinton tie. International arms dealers? The Kremlin? Uranium production? Human rights violators? Known felons? All can be connected to the Clintons.

As with the Duffy accusation, the allegations are often dubious. But Clinton and her husband have only themselves to blame for making themselves vulnerable to guilt-by-association attacks. They have managed to make Hillary Clinton conspicuously out of tune with the mood of the 2016 electorate: At a time of rising populist backlash against Wall Street, inequality and wealth-purchased privilege, there is no Democrat more closely tied to the rich and the powerful than Clinton. At a time when Democrats need to draw contrasts with Republicans by sticking up for the little guy, Clinton’s solicitation of — and favors for — the powerful make her an inauthentic messenger.

A New York Times/CBS News poll this week found that 65 percent of Americans think the gap between rich and poor is a problem that needs immediate attention, and the concern exists among Republicans and independents as well as Democrats. By a lopsided margin of 74 percent to 3 percent, Americans said corporations have too much influence on American life and politics rather than too little.

This presents a natural opportunity for Democrats — or it would if they weren’t almost as closely tied to the rich as Republicans. An Election Day poll conducted for the AFL-CIO last year found 80 percent of voters agreeing with the sentiment that “politicians from both the Democratic and Republican parties do too much to support Wall Street financial interests and not enough to help average Americans.”

As The Post has documented, the Clintons’ charitable efforts have been closely tied to the considerable fortune they amassed for themselves. Bill Clinton was paid at least $26 million in speaking fees by entities that were major donors to the foundation. The foundation has also been good for the balance sheets of Clinton friends such as Sidney Blumenthal, who received about $10,000 a month from the foundation while providing his thoughts on Libya to then-Secretary Clinton.

The vast array of contributors to the foundation (and those who paid the Clintons to give speeches) gives endless material to critics, and to the media: the uranium mining company that funneled money to the foundation while it had business before the State Department; the State arms-sale approvals for foundation contributors; the scores of foundation donors who lobbied State; the Canadian affiliate of the foundation that didn’t disclose its donors; the Keystone XL pipeline bankers who paid the Clintons to speak; the fees charged to a charity for tsunami victims; the use of an unreported pass-through company; Hillary Clinton’s brother’s ties to a Haitian gold mine; the money from countries with poor human-rights records; and contributions to the foundation from Qatar while Bill Clinton gave a boost to its controversial World Cup bid.

The Clintons’ defenders will say none of this is illegal, and that may be so. The problem is appearance. Clinton can talk all she wants about income inequality and reducing the influence of money in politics, but her recent experience makes her seem insincere.

Twitter: @Milbank

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