Democratic presidential candidate Sen. Elizabeth Warren, D-Mass., speaks at the Heartland Forum held on the campus of Buena Vista University in Storm Lake, Iowa, Saturday, March 30, 2019.

Presidential candidate Sen. Elizabeth Warren, D-Mass., released her 2018 tax returns on Wednesday, revealing an income of nearly $1 million last year between her and her husband, Bruce.

Warren, a consumer advocate who has made combating corruption one of her signature policy priorities, used the release of her returns to champion a sweeping anti-corruption bill she introduced in the Senate that requires the IRS to release eight years of returns filed by candidates for president and vice president.

"I've put out eleven years of my tax returns because no one should ever have to guess who their elected officials are working for," Warren said. "Doing this should be law."

Warren and her husband, a professor at Harvard, paid more than $200,000 in taxes on about $900,000 in income last year, the returns show.

Here's what else the returns showed:

Warren made about $325,000 from book sales in addition to her $175,000 salary from the Senate.

Bruce was paid about $400,000 from Harvard.

The couple paid about $46,000 last year for a solar energy installation on their home in Massachusetts, and received about $15,000 in tax credits.

The couple donated more than $50,000 to charity.

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Her disclosure comes as President Donald Trump fights congressional efforts brought by House Democrats to force the release of his returns. Trump has gone back and forth on whether he will release his returns, though his acting chief of staff recently said they will never be made public.

Trump has said that their release would impact an ongoing audit, though the IRS has said that audits do not prevent individuals from releasing their tax information.

The move also put more pressure on rivals who have not yet released their own, as other top Democratic 2020 contenders are still holding out. Sen. Bernie Sanders, a Vermont independent, has said that his returns will be public by April 15.

Sen. Cory Booker, D-N.J., former Texas congressman Beto O'Rourke, and South Bend, Indiana, Mayor Pete Buttigieg are among other top contenders who have yet to make their latest returns public, although those returns are not due to the government until Monday.

Sen. Kirsten Gillibrand, D-N.Y., was the first Democratic presidential contender to release her 2018 returns, doing so late last month.

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