ABC News(NEW YORK) — Thousands of protesters at Tax Day marches Saturday in cities from Washington, D.C., to Denver to Los Angeles are calling on President Trump to release his tax returns.

Trump is the first U.S. president and the first major party nominee in four decades to refuse to release his full tax returns to the public.

Organizers said Saturday’s protests, dubbed the Tax March, were scheduled in nearly 150 cities, and stemmed from the women’s march that took place the day after Trump’s inauguration.

As a candidate, Trump said he wasn’t releasing his tax returns because he was under audit. He later said that voters don’t care.

“We do care. We want to see his taxes,” said Ann Demerlis, who was among hundreds who marched in Philadelphia from City Hall to an area in front of historic Independence Hall.

“It’s possible that he can now show his taxes, because his current taxes are not being audited,” said Demerlis, who carried a sign saying, “Follow the Money.”

Trump’s break with precedent has raised questions about possible conflicts of interest.

Senate Democratic leader Chuck Schumer of New York has said Trump’s refusal to release his returns could hinder Republicans’ prospects for a rewrite of the tax code. And Democratic U.S. Sen. Elizabeth Warren of Massachusetts on Friday posted an online video urging Congress to force Trump to release the returns.

Republicans have rebuffed Democrats’ efforts to get the House Ways and Means Committee to act. It has legal authority to obtain confidential tax records, and could vote to make them public.

In Washington, D.C., on Saturday, the march began with a rally at the U.S. Capitol, where Sen. Ron Wyden called on Trump to “knock off the secrecy.” The Oregon Democrat said the people have “a basic right to know whether the president pays his fair share.”

The march was set to pass by the Trump International Hotel on Pennsylvania Avenue and concludes at the Lincoln Memorial.

This year’s National Tax Day, the IRS filing deadline for 2016 tax returns, is on Tuesday.

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