When Courtney Gore ran for a seat on her local school board in 2021, she warned about a movement to indoctrinate children with “leftist” ideology. After 2 1/2 years on the board, Gore said she believes a much different scheme is unfolding: an effort by wealthy conservative donors to undermine public education in Texas and install a voucher system in which public money flows to private and religious schools.

Gore points to West Texas billionaires Tim Dunn and brothers Farris and Dan Wilks, who have contributed to various political action committees that have poured millions into legislative candidates who have promoted vouchers. The men also fund or serve on the boards of a host of public policy and advocacy organizations that have led the fight for vouchers in Texas.

In recent years, the largesse from Dunn and the Wilks brothers has reached […]