Donald Trump’s critics have been calling for months on the Republican presidential nominee to release his tax returns, to no avail. Now, even Trump supporters are joining the chorus.

Rep. Mark Sanford( R-S.C .), a professed Trump backer( for now ), wrote a Sunday New York Times op-ed titled, “I Support You, Donald Trump. Now Release Your Tax Returns.”

Rep. Mark Sanford( R-S.C .) has called on Donald Trump to release his tax returns.

Sanford noted his continued ability to support Trump will “in part be driven by whether Mr. Trump maintains his term that he will release his taxation records.”

Sanford notes just two years earlier in just one of several instances Trump clearly stated he would have no problem releasing his tax returns.

During an interview with an Irish Tv station, Trump said, “If I decide to run for office, I’ll render my tax returns, absolutely and I would love to do that.”

Trump’s bombastic statements, Sanford argues, will be forgotten with hour, while the legacy of his actions will linger.

“Not releasing his tax returns would hurt transparency in our democratic process, and particularly in how voters evaluate the men and women vying to be our leaders, ” Sanford wrote.

Data compiled by the Tax History Project shows that every Republican nominee since Richard Nixon has made their tax returns public.

Trump has inflated asserts over the years about his personal net worth and charitable devoting two areas that could be cleared up by releasing his tax returns. But said he won’t build the documents public because he’s being audited by the IRS.

While the IRS has said an audit doesn’t prevent Trump from releasing the returns, Sanford, a former governor, was at least sympathetic to how unpleasant the process can be.

“I operated twice for governor of South Carolina, and I released my tax returns both hours. To be frank, it felt a little bit like a colonoscopy: I didn’t like it, but it was our tradition in South Carolina. The power of biding true to the precedent that had been set prevailed.”

Recent revelations about the finances of Trump campaign chairman Paul Manafort are likely to increase pressure on Trump to release his tax returns.

The New York Times reported on Sunday that a Ukrainian anti-corruption bureau observed Manafort’s name on a secret ledger used by the deposed, pro-Russia government of ex-Ukrainian President Viktor Yanukovych. The ledger proved pays totaling $12.7 million designated for Manafort from Yanukovych’s political party. Manafort was a top political consultant to Yanukovych for several years, but it’s not clear if he ever received the payments listed.

The financial and political ties of several Trump campaign aides and donors to entities associated with the Russian government have also raised questions about whether conflicts of interest are influencing the GOP presidential candidate’s opinions of U.S. policy toward Russia. Trump has suggested he would take a more conciliatory approach toward President vladimir putin, whose government has elicited Western sanctions and geopolitical isolation for its takeover of the Ukrainian peninsula of Crimea and support for an armed insurrection in eastern Ukraine.

An embarrassing hacker into the Democratic National Committee and presidential campaign of Hillary Clinton that is widely believed to be the work of the Russian government has also created distrusts about the Trump campaign’s Russian ties.

Trump himself has denied any investments in Russia or other fiscal connections to the country. His asserts are impossible to verify, however, without access to his tax returns.

Daniel Marans contributed reporting .

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