Fredreka Schouten

USA TODAY

WASHINGTON — In a major jolt of support for President Trump, the powerful political network overseen by conservative billionaire Charles Koch is launching a multimillion-dollar campaign to drive Trump's tax plan through Congress.

Koch, who viewed Trump's candidacy warily, now is racing to build public and congressional support for plans to overhaul the tax code. Trump's one-page tax blueprint, released last month, includes plans to slash the corporate tax rate, reduce taxes for high-income earners and abolish the federal estate tax.

The group plans to throw "the full weight of the network" behind the campaign with the goal of passing a tax overhaul this year, said James Davis, a top official in Koch's Freedom Partners Chamber of Commerce. Davis would not disclose a specific dollar amount but said the effort would include advertising and mobilizing grassroots activists.

The campaign is expected to last into the fall.

The chaos and controversy engulfing Trump's White House threatens to imperil his legislative agenda on everything from taxes to a plan to rebuild the country's infrastructure. But network officials see a window to push the tax plan this year, well in advance of the midterm elections that could risk Republican control of Congress.

"If you don't do it now, it becomes increasingly difficult," Davis said.

The network ranks among the most influential players in conservative politics with operations in 36 states and its own grassroots arm and for-profit data and marketing branches. In all, about 550 ultra-wealthy donors help finance the constellation of political and nonprofit groups associated with Koch and his brother David Koch.

Those groups plan to spend $300 million to $400 million on policy and political campaigns ahead of the 2018 elections.

Although Koch opposes Trump's travel bans and questions the president's skepticism of free-trade policies, the head of one the country's largest industrial conglomerates has praised Trump for several actions since taking office, including his move to dismantle "unnecessary" federal regulations.

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