CHICAGO — At the start of the Democratic National Convention on Monday, Vice President Harris called for a corporate tax increase while the party’s presidential nominee unveiled her first major proposal to raise government revenue.

The Harris team confirmed to Fox News that the vice president is proposing to raise the tax rate paid by large corporations from 21 percent to 28 percent, calling it a “fiscally responsible way to put money back in the pockets of working people and ensure that billionaires and large corporations pay their fair share.”

“As president, Kamala Harris will focus on creating an economy of opportunity for the middle class that strengthens their economic security, stability and dignity,” campaign spokesman James Singer said in a statement.

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Democratic presidential candidate Vice President Harris speaks at the Hendrick Center for Automotive Excellence on the Scott Northern Wake Campus of Wake Tech Community College in Raleigh, NC on August 16, 2024. (ALLISON JOYCE/AFP via Getty Images)

If this move becomes law, it could raise hundreds of billions of dollars, according to forecasts by the nonpartisan Congressional Budget Office.

The announcement comes as Harris is unveiling details of how she would govern if elected president and how she would seek to fund the expensive ideas she proposed last week, including expanding the child tax credit, lowering the cost of homeownership and reducing medical bills.

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The announcement would also represent a significant rollback of the 2017 tax cuts, the major national law passed under former President Trump’s administration that dramatically cut the corporate tax rate from 35 percent to 21 percent.

Trump has promised to cut taxes if he returns to the White House.

“Our plan will cut taxes massively,” Trump said Monday at a campaign rally at a factory in York, Pennsylvania. “I’ve given you the best tax cut in history.”

Republican presidential candidate and former President Trump speaks at a Precision Components Group campaign rally in York, Pennsylvania on August 19, 2024. (AP Photo/Matt Slocum)

And he signaled that he aims to use tariffs against both competitors and allies by pushing for legislation called the Trump Reciprocal Trade Act.

But the Harris team says Trump’s planned tariffs on foreign goods would “punish the American middle and working class so he can cut taxes on the richest Americans.”

Parts of the Trump tax cuts expire at the end of 2025, which will spark a major debate next year about which parts should be extended.

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Jason Miller, a senior adviser to the Trump campaign, referenced Harris’ proposal in a social media post, writing: “Bye-bye economic growth, hiring, investment, expansion, onshoring and so much more!”

Harris’ new stance is in line with President Biden’s recent budget proposal, which also calls for an increase in the corporate tax rate to 28 percent.

The Democratic National Convention (DPNC) began on August 19, 2024 at the United Center in Chicago. (Fox News/Paul Steinhauser)

Harris replaced Biden at the top of the 2024 Democratic ticket four weeks ago after Biden announced he was withdrawing his re-election bid and supporting his vice president as his successor.

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But veteran Republican consultant and strategist Alex Castellanos told Fox News that such proposals would do Harris no favors at the ballot box.

“She doesn’t need the spotlight for herself or her policies. She has too many issues on both sides. And if she supports a corporate tax increase, that’s a job killer. You don’t have to hurt working people directly. You just have to hurt the companies that working people work for,” Castellanos said.

Fox News’ Emily Reynolds contributed to this report.

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