Trump's Tax Returns Remain Mystery as Election Day Looms

— -- Election Day is just hours away and one of the campaign's greatest mysteries remains unsolved: Donald Trump never released his tax returns.

The Republican presidential candidate's campaign was full of firsts, but he also earned the title of the first major party candidate not to release his tax returns since President Gerald Ford.

Trump repeatedly claimed that his taxes were under routine audit and said that he would release them as soon as the audit was completed. He later said that he would do so if Hillary Clinton released the 33,000 emails that she deleted.

During a Republican primary debate in February, Trump said that he wanted to release the returns but an audit was being conducted.

Several tax experts told ABC news that there are no legal reasons barring a subject of an audit from releasing their own returns.

Three pages that appeared to be from Trump's 1995 state tax filings were anonymously sent to The New York Times in October and they reportedly show that he declared a $916 million loss.

The paper claimed that the loss could have allowed Trump to avoid paying federal income taxes for 18 years.

Trump's camp did not dispute the documents, but said he paid hundreds of millions of dollars in other taxes over the years.

The topic came up in the first presidential debate as well, with Clinton suggesting a few reasons Trump might be refusing to release his returns, and after she charged that he didn't pay federal income taxes in some years, he couldn't stop himself from boasting, "That makes me smart."

Trump's running mate, Indiana Gov. Mike Pence, released 10 years of his family's tax returns in September.

By contrast, Hillary Clinton released her family's tax returns from 2007 through 2014, and they had previously released returns dating back to 1977. Her campaign states that their family paid an effective tax rate of 35.7 percent in 2014.

Clinton's campaign his criticized Trump's lack of transparency, speculating that the tax returns could reveal Trump's net worth is lower than he claims or he's given less to charity than he says.