Hillary Clinton promised at a fundraiser Friday evening that her economic agenda would not add a penny to the national debt, which currently stands at $19.7 trillion.

"When people ask me, 'So how are you going to pay for infrastructure jobs and paid family leave?', I say, 'Well, I'm telling you how I'm paying for everything," she said at a campaign event in Seattle, drawing a contrast with GOP nominee Donald Trump.

"I am not going to add a penny to the national debt," she vowed. "We're going to go where the money is. We're going to make the wealthy pay their fair share, and we're finally going to close those corporate loopholes."

The Democratic nominee often promise on the campaign stump that she will fund her White House agenda by going after the very wealthy.

"I'll tell you how we're going to pay for it," she said in August, referring specifically to her proposed economic policies. "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."

Despite her pledge, a study out this week said Clinton's plan to tax more and spend more may in fact increase the national debt by hundreds of billions of dollars. That study said she wants to $1.4 trillion in new tax revenue over a 10-year period, and spend about the same amount. But when dynamic scoring is used, her tax hikes could slow the economy down to the point that only $663 billion is collected, not enough to offset her spending plans.

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.

Her promise to go after the very wealthy and crack down on Wall Street has drawn criticism from those who've noted she made millions of dollars giving closed-door speeches to top financial firms, including Goldman Sachs and Bank of America.

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. Much of that came from paid speeches, and many of those speeches were to wall Street firms.