Hillary Clinton promised Tuesday that she would pay for her ambitious White House agenda by hitting up the wealthy.

"I'll tell you how we're going to pay for it," she said Tuesday in Pennsylvania, referring specifically to her economic agenda. "We're going where the money is. We are going after the super wealthy, we are going after corporations, we are going after Wall Street so they pay their fair share."

Clinton has been under pressure from Democrats to pursue a more progressive agenda, especially after Sen. Bernie Sanders, I-Vt., gave her a close primary race with a platform of higher taxes and an expanded federal government.

The Democratic presidential candidate has also been criticized for claiming she will be tough on Wall Street, even after members of the financial industry, including Goldman Sachs and Bank of America, have compensated her handsomely for delivering speeches.

Clinton's lucrative speaking gig came under close scrutiny during the Democratic presidential primary after Sanders called on her repeatedly to release the text of her paid remarks to various Wall Street firms.

She refused then, and she refuses now to release the text of her Wall Street speeches.

A review of the Clintons' 2015 tax returns show they took in a combined $6.72 million from paid speeches. Their 2015 tax returns, which were released last week, also showed they paid an effective federal tax rate of 34.2 percent, and that they had an adjusted gross income of $10.6 million.

This is a notable decline from 2014, when Hillary Clinton alone took in $10.5 million in speaking fees, combining with Bill Clinton's $9.7 million on the way to an adjusted gross income of nearly $28 million. In 2013, Hillary Clinton earned $9.6 million from speaking to various groups.

There's a reason for the drop of more than $17.4 million between 2014 and 2015: Hillary Clinton stopped giving paid speeches after she announced her candidacy in April of last year.

Still, Bill Clinton drew in $5.25 last year, and Hillary Clinton took in $1.47 million.