The bellwether conservative group Club for Growth, which endorsed former Texas Solicitor General Ted Cruz last summer in his bid to succeed retiring U.S. Sen. Kay Bailey Hutchison, has bought advertising time on cable systems across Texas to attack Cruz's chief opponent in the GOP primary, Lt. Gov. David Dewhurst.

The two 15-second spots — part of a $500,000 spend targeting candidates in Texas, Michigan and Pennsylvania — focus on Dewhurst's record on taxes and health care. Both accuse him, pejoratively, of being a "moderate."

"David Dewhurst is wrong for conservatives and he’s wrong for Texas,” said Club for Growth President Chris Chocola, a former Indiana congressman, in a statement emailed to reporters.

“This is just the first of many false attacks by Washington insider groups aiming to distort David Dewhurst’s conservative record and handpick a candidate they can control," Dewhurst campaign spokesman Enrique Marquez told the Tribune. "The fact is that David has been one of the strongest advocates for Texans in cutting taxes, reducing spending and balancing the budget.”

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Barney Keller, the communications director for Club for Growth, told the Tribune that his organization intends to produce more ads attacking Dewhurst between now and the April 3 primary. "This is just the beginning of our efforts in Texas," Keller said.

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