Trump tweeted Sunday: "I did what was an nearly an impossible thing to do for a Republican-easily won the Electoral College!" "I'm wondering if you'll take the initiative to have him release those returns", the constituent asked, "so we can see what kind of connections he has with different countries around the world, and what tax proposals would personally benefit him and his family".
And though he and his surrogates have said often that he would release them when the audits were complete, there's no way to independently verify that the audits of his returns from years past are still ongoing.
The comments com after American TV channel MSNBC revealed it had seen a tax return summary for the billionaire tycoon for 2005.
Ilene Singh said she and her friend, Geraldine Markowitz, took a bus from New Jersey to join the crowd and "say we care" about Trump's taxes.
Trump was the first major-party nominee in more than 40 years not to release his returns and he reneged on a campaign commitment to release them.
Ms McCaughey told BBC Radio 4's Today programme: "Most people who run for president are just career politicians, they make their money giving speeches and writing books, they have very very simple tax returns".
Violence erupted at one of those rallies, and many people were arrested in Berkeley, Calif., where groups that support and oppose the president clashed. He later said that voters don't care.
The protesters gathered at a rally at Bryant Park, near the New York City Public Library.
"Without seeing his taxes, we'll never really know who he's working for", said Dinkin, who expects the marches to draw at least 100,000 protesters.
Organizers say marches are planned Saturday in about 150 cities, including Washington, D.C., where theirs will begin with a rally at the U.S. Capitol.
Pushing her walker, Karin Arlin, 85, a Holocaust survivor who came to the US from Germany when she was 9, said she's also anxious about the direction of the country.
Kinzinger's comments came after press secretary Sean Spicer dealt another blow to transparency advocates Monday, announcing that Trump's 2016 tax returns are under audit and therefore would not be released.
"If he thinks he can get away with playing king, he's got another thought coming", Waters said. Trump's break with precedent has raised questions about possible conflicts of interest.
Republicans also have rebuffed Democrats' efforts to get the House Ways and Means Committee to act.