The 30-second ad from Texans for a Conservative Majority relies largely on reporting done by the Houston Chronicle raising questions about Stockman’s campaign donations and business dealings.
The ad will run in the Houston and Beaumont-Port Arthur media markets, according to Lisa Boothe, the group’s spokeswoman.
Austin lawyer Randy Cubriel launched the PAC early last year. Last month, it paid $70,000 for online ads promoting the group’s website, shadystockman.com, according to FEC records.
Stockwood, a Friendswood Republican, launched a surprise primary challenge against Cornyn last month.