The first television ad from a political action committee supporting U.S. Sen. John Cornyn’s re-election bid is focused on ethical issues related to U.S. Rep. Steve Stockman.

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.

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