The Americans for Prosperity, a nonprofit conservative organization, announced Monday a $20 million nationwide ad campaign advocating for Congress to renew President-elect Donald Trump's tax cuts, passed during his first term.

This is the largest effort by AFP, backed by the Koch family, to support Trump's second-term agenda, with ads planned for all 50 states, the organization said.

AFP said it will conduct over 1,000 meetings with congressional offices on Capitol Hill and share testimonials from American families and businesses that would suffer if Congress failed to renew the Tax Cuts and Jobs Act, passed in 2017. The tax cuts expire at the end of the year.

"AFP will help all Americans understand what is at stake for their tax bill and family budget," the group said in a statement.

The organization said it would "hold accountable members who do not support this agenda."

AFP warned that if Congress fails to renew the tax cut, millions of Americans will pay an average of $1,500 more in taxes per year, with many states paying higher — $2,394 per year in Pennsylvania, $2,732 in Arizona and $3,523 in Nevada.

House Republicans are working on how to extend $4.6 trillion worth of provisions from the cuts before they expire, Politico said. Deficit hawks in Congress have argued any tax cuts must be paired with corresponding spending cuts, according to Politico.

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