At a campaign rally Thursday, presumptive Republican presidential nominee Donald Trump claimed credit for a common refrain in the White House race — a bit of rhetoric voters increasingly hear from both sides of the political aisle.

“It’s a rigged deal,” he said of the American political system, and specifically the Democratic presidential primary. “You notice I started talking and using the word ‘rigged,’ right? About four months ago. Nobody used the word ‘rigged.’ Now everybody’s calling it rigged. … I want to have that phrase coined.”

Of course, Trump didn’t actually coin anything here. The charge that “the system is rigged” is a longtime favorite of Massachusetts Sen. Elizabeth Warren — yes, “Goofy Elizabeth Warren” herself — and each of the three leading Democrats who ran to replace President Barack Obama adopted similar rhetoric.

Martin O’Malley said the primary debates were rigged.

Bernie Sanders said the debates and the superdelegates were rigged, along with the entire economy.

Ultimately, Hillary Clinton even agreed on that last point.

There’s a reason for all of this — and for Trump’s recent digression: these arguments have taken hold with the American people and become central to this election. Last November, citing Public Religion Research Institute data, the Washington Post’s Harold Meyerson summarized it thus:

Across party lines, Americans believe that our economic system is rigged to favor the wealthy and big corporations, and that our political system is, too — so much so that by nearly a 2-to-1 margin (64 percent to 36 percent), Americans believe their “vote does not matter because of the influence that wealthy individuals and big corporations have on the electoral process.”

Just last month, there was fresh evidence from a Reuters poll: “More than half of American voters believe that the system U.S. political parties use to pick their candidates for the White House is ‘rigged’ and more than two-thirds want to see the process changed,” according to the survey.

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