A report in the New York Times says a $916 million loss in the '90s might have allowed Donald Trump to legally avoid paying any income taxes for almost two decades. (Sarah Parnass/The Washington Post)

A report in the New York Times says a $916 million loss in the '90s might have allowed Donald Trump to legally avoid paying any income taxes for almost two decades. (Sarah Parnass/The Washington Post)

Donald Trump is scrambling to rescue his campaign after a week in which the Republican nominee’s White House hopes were effectively set ablaze by his own erratic behavior and the discovery that he may not have paid federal income taxes for as many as 18 years.

Reeling from a New York Times report that Trump may have canceled out years of income taxes by declaring a $916 million loss on his 1995 return, his allies mounted a vigorous defense Sunday by arguing that the revelation was proof of the businessman’s ­“genius.”

With only five weeks until Election Day and voters in some states, including battleground Iowa, already beginning to cast ballots, Hillary Clinton and her campaign will labor this week to keep Trump in a downward trajectory.

But Trump hopes to recover by driving a contrast, starting Monday at campaign rallies in Colorado, between how he and Bill and Hillary Clinton made their fortunes. Trump plans to argue that he built a global real estate empire and employed thousands of people, while the Clintons got rich delivering paid speeches to financial institutions and other corporate interests, according to his aides.

“We’re going to shine the spotlight very brightly on how the Clintons made their money,” senior adviser Jason Miller said. “They were so broke when they left the White House that they couldn’t pay either of their mortgages, they haven’t invented anything, they haven’t won Powerball, they haven’t so much as billed a single hour of legal work, yet they’re worth a couple hundred million dollars.”

Following a New York Times report alleging that Donald Trump could have avoided paying federal income taxes for 18 years, former New York mayor Rudolph W. Giuliani and New Jersey Gov. Chris Christie on Oct. 2 said Trump’s handling of tax laws was “genius.” (The Washington Post)

Asked about Trump’s plans to portray Clinton as a compromised multimillionaire, communications director Jennifer Palmieri laughed.

“He has a lot to answer for,” Palmieri said, alleging that Trump’s businesses have cheated contractors and outsourced jobs.

[Will Trump shift gears in time for the next debate?]

Clinton plans to deliver a sweeping economic address Monday in Toledo, where she is expected to highlight inherent unfairnesses in the economy that allow some businesses to take advantage of ordinary Americans. Clinton also will hold a town hall meeting Tuesday in the Philadelphia suburbs, where she and daughter Chelsea will make a pitch to female voters by touting child-care initiatives.

Clinton will get a lift from an array of star surrogates — including President Obama, first lady Michelle Obama and Sens. Bernie Sanders (Vt.) and Elizabeth Warren (Mass.) — who are fanning out across swing states in the South and industrial Midwest to solidify Clinton’s support among young and minority voters and convince anyone who is undecided that Trump is temperamentally unfit for office.

“Donald Trump’s campaign is showing all the signs of entering a spiral,” Clinton spokesman Brian Fallon said. “At a very critical stage in the campaign, he is making our own arguments for us about his lacking the temperament to be president. As he continues to lash out and go low, as he flails to keep things together, we are intending to focus on her affirmative vision.”

The Clinton team is taking little for granted, acknowledging that momentum could shift back in Trump’s favor. “We certainly are planning for that. We are not expecting that he stays in the frame of mind he was at 3:20 a.m. Friday,” Palmieri said, referencing an erratic series of overnight tweets by Trump last week.

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On Tuesday night, the task of generating needed momentum for the Republican ticket will fall to Trump’s vice-presidential running mate, Indiana Gov. Mike Pence, who will debate Clinton’s running mate, Sen. Tim Kaine (Va.), for the first and only time at Longwood University in rural Farmville, Va.

But the only person who can resuscitate Trump’s candidacy is Trump. The proudly unpredictable and often undisciplined nominee had been surging in the polls last month and turned the race with Clinton into a dead heat, only to fall into what was perhaps the most difficult week of his general-election campaign.

Trump turned in a shaky debate performance, feuded for days with a Latina former beauty queen over her weight gain, slipped in national and state polls, fired off a series of middle-of-the-night Twitter tirades and speculated without evidence in a rambling speech Saturday night that Clinton may have cheated on her husband.

[As news of Trump’s taxes breaks, he goes off script at a rally in Pennsylvania]

“What we’re seeing is somebody who’s blowing himself apart in real time,” said Peter Wehner, who served in the administrations of the last three Republican presidents and who opposes Trump. “It’s a pretty extraordinary thing to see. It’s a political death wish, as if at some deep level he doesn’t want to be president.”

Wehner added, “It’s gnawing on him that he could become what he has contempt for, and that is a loser.”

Mo Elleithee, a Democratic strategist who runs Georgetown University’s Institute of Politics and Public Service, said, “Political operatives and strategists are going to study this week for generations as the textbook case of self-sabotage.”

The best opportunity for Trump to rebound before a massive national audience is likely to be next Sunday, when he debates Clinton for the second of three times, at Washington University in St. Louis.

Ahead of the first debate, Trump refused to do mock debates and did not study as rigorously as Clinton. In preparation for the St. Louis debate, Trump has blocked off time in his schedule this week for preparation sessions.

Trump spent Sunday at his golf club in Bedminster, N.J., huddling with former New York mayor Rudy Giuliani and New Jersey Gov. Chris Christie and other advisers, as well as family. Over salads and sandwiches, they helped coach Trump on the town hall format in St. Louis, when unlike in the first debate the candidates will move freely onstage and field questions from voters in the audience.

“He’s in a good mood and feeling very comfortable,” Giuliani said of Sunday’s session.

The political talk shows Sunday were dominated by discussion of the Times report, based on portions of Trump’s 1995 tax returns mailed to the newspaper anonymously, that showed he may have taken advantage of special rules for real estate investors that legally allowed him to use his $916 million loss to offset $50 million a year in taxable income for as many as 18 years.

Trump’s year-by-year returns would show how much he paid in federal income taxes, but he has refused to release them. For four decades, all presidential nominees have released years’ worth of tax returns, including Clinton.

[What we know about Donald Trump’s income tax history, by year]

The Clinton team moved Sunday to exploit the tax discovery to underscore their central argument against Trump’s qualifications and temperament. Clinton officials argued that he took advantage of loopholes that ordinary workers cannot.

Senate Minority Leader Harry M. Reid (D-Nev.), who has sparred with Trump over his taxes and business record, issued a caustic statement on Sunday: “Trump is a billion-dollar loser who won’t release his taxes because they’ll expose him as a spoiled, rich brat who lost the millions he inherited from his father,” he said.

Trump’s leading surrogates, Giuliani and Christie, offered a different assessment. They said Trump’s avoidance of taxes demonstrated his business acumen and smarts. They did not dispute the Times’s findings, nor has Trump’s campaign.

“He’s a genius — absolute genius,” Giuliani said on ABC’s “This Week.” “This was a perfectly legal application of the tax code, and he would’ve been a fool not to take advantage of it.”

Christie, who chairs Trump’s presidential transition project, proclaimed on “Fox News Sunday” that “this is actually a very, very good story for Donald Trump.”

“What it shows is what an absolute mess the federal tax code is, and that’s why Donald Trump is the person best positioned to fix it,” the governor added. “There’s no one who’s showed more genius in their way to move around the tax code.”

Trump’s tax plan — which would cut rates for high-income people like him and eliminate the “carried interest” loophole that benefits hedge fund managers, among other things — does not address the rule he may have taken advantage of with his tax filings. He and his campaign have not said whether Trump plans to eliminate or change it.

[The New York Times risked legal trouble to publish Donald Trump’s tax return]

Central to Trump’s candidacy has been the idea of him as a successful businessman. Political analysts said the revelation that he declared a nearly $1 billion loss when his real estate company almost collapsed threatens to undercut his credibility in business.

Clinton’s supporters also held up Trump’s apparent exploitation of tax laws to avoid paying taxes as an example of a rigged tax code, which allows billionaires to use loopholes that they said were unavailable to ordinary workers.

“Trump goes around and says: ‘Hey, I’m worth billions! I’m a successful businessman! And I don’t pay any taxes. But you — you make 15 bucks an hour — you pay the taxes, not me,’ ” Sanders said on CNN. “This is exactly why so many millions of Americans are frustrated, they are angry, they are disgusted.”

Anne Gearan, Robert Costa, Jenna Johnson and Sean Sullivan contributed to this report.