Nike co-founder and chairman emeritus Phil Knight has written the campaign of state Rep. Knute Buehler (R-Bend) a $1 million check for his November general election challenge to incumbent Gov. Kate Brown.

Although the campaign has not yet disclosed the check in the state campaign finance filing system, WW has learned that Knight has written it—and that the Buehler campaign has in turn committed to a television ad buy far in excess of the $645,000 it currently has on hand. (The campaign has 30 days from receipt to disclose the contribution.)

Buehler's campaign spokewoman, Monica Wroblewski, declined to confirm Knight's contribution.

"Our campaign does not discuss our donors or our donations," Wroblewski said in a statement Thursday evening.

Knight's check is the largest individual contribution to an Oregon candidate since the state began keeping electronic campaign records in 2006. (New York billionaires Michael Bloomberg and John Arnold have each made contributions of $1 million or more to Oregon ballot measures.)

Although Knight, 80, is a registered Republican, he has supported candidates of both major parties in previous gubernatorial elections.

In 1986, for instance, he supported Neil Goldschmidt, a Democrat, in his race against Republican Norma Paulus. (Goldschmidt was a former Nike employee.) In 2010, he supported Republican Chris Dudley, giving the former NBA player $400,000 for his race against Democrat John Kitzhaber. After Kitzhaber narrowly defeated Dudley, Knight gave the Democrat $250,000 in his successful 2014 re-election campaign.

The new contribution follows a $500,000 check Knight wrote Buehler in August 2017.

Knight's money is a big part of Buehler's campaign. With the new check, since the beginning of 2017, Buehler has raised $5.75 million—22 percent of it from Knight. Over the same period, Brown has raised $8.25 million. Her biggest individual contributor in that period is Steve Silberstein, a California tech investor, who gave her $100,000.

Among Brown's other supporters: Nike, Inc., the company Knight co-founded in 1964. The company has given the governor a total of $35,000 so far this year.

Knight has long gone his own way on political contributions, however, so it's not entirely surprising that he and the company where he made his fortune are on opposite sides of the governor's race.

Knight stepped down as Nike chairman in 2016, although he still attends board meetings a non-voting observer. He could not be reached for comment.