The political arm of the conservative Koch network will announce Wednesday that it is endorsing Republican Walker Stapleton in the Colorado governor’s race — and may spend as much as $1 million to help get him elected.



Americans for Prosperity-Colorado told The Colorado Sun that it would put its “full weight” behind Stapleton, the two-term state treasurer, mobilizing its volunteers and spending big money to boost his campaign.



“Walker Stapleton has been working here in Colorado for the last eight years and understands the challenges our communities face and how to overcome them,” said Jesse Mallory, AFP’s state director. “He’ll defend TABOR, work to expand educational freedom, and ensure special interests don’t limit our energy sources.”



The endorsement is not new — The Colorado Sun first reported the pending announcement in The Unaffiliated newsletter in August.



But the direct spending in the state-level race through an independent expenditure group is a new detail — and unprecedented for the the organization tied to billionaire Charles Koch. It plans to spend upper six-figures on the campaign and may top out near $1 million, officials said.



AFP Colorado is just the latest political committee to come to Stapleton’s defense in a governor’s race in which Democratic rival Jared Polis is spending millions from his own pocket.

For a roster of political groups spending in the Colorado governor’s race, check out The Sun’s guide here.