AUSTIN, Texas (AP) - Former Dallas Mayor and senatorial candidate Tom Leppert has endorsed David Dewhurst for the U.S. Senate.

Leppert announced the decision late Tuesday after the lieutenant governor finished his final televised debate with Ted Cruz.

Leppert came in third in the May Republican primary race to replace retiring U.S. Sen. Kay Bailey Hutchison. Dewhurst and Cruz are competing in a July 31 runoff. Early voting begins on Monday.

Tuesday night Dewhurst and Cruz traded increasingly pointed attacks. Dewhurst struggled during the debate to make a point about improving American health care, while Cruz found it difficult to balance his desire for a border fence and the rights of property owners along the border.

Cruz attacked Dewhurst for his record in office, while Dewhurst tried to paint Cruz as hired-gun attorney.

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