Vermont U.S. Sen. Bernie Sanders undermined a key Obama administration talking point Monday when he said the actual unemployment rate in the U.S. is double what the federal government claims.

“When you talk about the economy we also have to have an honest assessment of unemployment in America,” Sanders told a crowd of 7,500 gathered at a presidential campaign rally in Portland, Maine.

“Once a month the government publishes a set of figures, and the last figures they published said that official unemployment was 5.4 percent,” the Democratic nominee continued, slightly misstating the Labor Department’s most recent report which put June’s unemployment rate at 5.3 percent.

“But there is another set of government statistics,” Sanders continued, “and that that real unemployment if you include those people who have given up looking for work and the millions of others who are working part-time 20, 25 hours a week when they want to work full-time, when you all of that together, real unemployment is 10.5 percent.”

That dose of reality is like a wet blanket on President Obama’s recent claims that the economy is improving.

“This is progress,” Obama said of the most recent unemployment number in a speech last week in Minnesota. “Step by step, America is moving forward. Middle class economics works.”

While Sanders is no conservative — he is listed as an Independent and calls himself a socialist — his claim that the actual unemployment rate is far higher than advertised is something heard most often, at least during Obama’s tenure, from the right.

WATCH (at 1:11:10):

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