"I would not be surprised if the official end of the U.S. recession ends up being, in retrospect, dated sometime this summer," he said June 8 during a lecture in London.
However, Krugman argues people didn't listen to his entire speech, which included dire predictions about lingering unemployment.
"There's a big difference between the end of a recession, which is really only when some things start to turn up, and the return to prosperity," Krugman told ABC News. "I think what people don't get is the difference between the end of a recession in a technical sense and actual recovery, which matters to people."
Some economists dismiss Krugman's calls for more government spending to stimulate the economy.
"His views about the impact of government spending on the economy are very different than those held by the majority of economists who are currently doing research on this topic," said UCLA economic professor Lee Ohanian, who argues the focus should be on reforming the banking system.
Particularly troubling, Ohanian said, is Krugman's focus on Keynesian economics, which focuses on public sector policies to stabilize the economy.
"A lot of what I see in his columns and in his blog is using economics from 70 years ago," Ohanian said," He likes to cite Keynes and we stopped teaching Keynes decades ago because like every other science, economics moves forward."
Krugman admits he is doing little research these days, preferring instead to hold Washington accountable through his blog and column for what he sees as misguided public policies.
His most fervent fans say his biggest strength is in translating complex ideas into simple and entertainingly pointed prose.
"He is incredibly good at boiling complex problems down to the simplest terms and explaining them clearly," said Maurice Obstfeld, economics professor at the University of California at Berkeley.
Krugman recently accused 212 members of the House of Representatives, who voted against the administration's climate change bill of 'betraying the planet" and engaging in "a form of treason."
He's also derided the president for not pushing hard enough for a large public option for health care reform.
"We knew that the health care plan was not going to be a reformer's ideal," Krugman said. "What we don't know is how far it will stray from the reform ideal. And I'm not saying it has to be perfect."
The biggest question, Krugman said, is whether the Obama administration will "back down" at crucial moments.
"People like me are trying to hold their feet to the fire," Krugman said.
He rails against arguments made by conservatives, like former Reagan speechwriter and Wall Street Journal columnist Peggy Noonan, that the Obama administration's multiple-pronged agenda is moving too fast for the public.
"Paul, if you just limit this conversation to taxes alone, you have some sense that people, normal humans in America, might be getting a little bit nervous about health care and energy care and all of this stuff," Noonan argued on "This Week" Sunday.
"Without getting into the weeds, you have got to assume it's going to cost money," Noonan argued. "At a certain point, you've got to realize, people are going to say, whoa, this is no good."
But Krugman argues "the weeds" are exactly where the health care reform debate should be.