On the trail

The New York Post, which has endorsed Donald Trump, published a fully nude photo of Melania Trump on its Sunday front page. The photo was originally taken for and published in a 1996 edition of Max Magazine, a defunct French magazine. In a statement, Donald Trump said, "Melania was one of the most successful models and she did many photo shoots, including for covers and major magazines. This was a picture taken for a European magazine before my knowing Melania. In Europe, pictures like this are very fashionable and common."

Hillary Clinton received a surge of support after the Democratic National Convention, according to a new national poll that showed her opening a lead against Donald Trump. The CBS News survey released Monday shows 46 percent of registered voters backing Clinton and 39 percent supporting Trump, the GOP nominee. That represents a 4-percentage-point bounce for Clinton, who was deadlocked with Trump after the Republican National Convention, which gave Trump a 2-point increase.

Donald Trump suggested Monday that he fears the general election "is going to be rigged" — an unprecedented assertion by a modern presidential candidate. Trump's extraordinary claim was not backed up with any immediate evidence. "I'm afraid the election is going to be rigged, I have to be honest," the Republican nominee told a town hall crowd in Columbus, Ohio. He added that he has been hearing "more and more" that the election may not be contested fairly, though he did not elaborate further. Trump made the claim after first suggesting that the Democrats had fixed their primary system so Hillary Clinton could defeat Bernie Sanders. Trump has previously backed up that thought by pointing to hacked DNC e-mails that appear to indicate a preference for Clinton.

Warren Buffett suggested that fellow billionaire Donald Trump is afraid to release his tax returns.

At an event with Hillary Clinton in Omaha, Buffett criticized Trump for breaking with decades of presidential campaign tradition by keeping secret documents that can reveal much about a candidate's charitable giving, assets and spending priorities. Trump says he'll release the returns after the IRS is finished auditing him. But Buffett suggested the real reason is fear, saying, "You're only afraid if you have something to be afraid of." He added that he would be delighted to meet Trump between now and the election. "I'll bring my tax return, he'll bring his tax return … and just let people ask us questions."

Clinton has released eight years of recent tax filings.

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