A natural gas drilling rig just east of downtown Fort Worth, Texas. A new decade-long study finds the region's Barnett Shale formation has sufficient gas reserves to last another 25 years. David Kent/MCT/Landov/Fort Worth Star Telegram hide caption

itoggle caption David Kent/MCT/Landov/Fort Worth Star Telegram

George P. Bush speaks during the 2011 Republican Leadership Conference in New Orleans. Justin Sullivan/Getty Images hide caption

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Sen.-elect Ted Cruz of Texas answers a question from a television reporter on Nov. 6 in Houston. David J. Phillip/AP hide caption

itoggle caption David J. Phillip/AP

David Thweatt, the school superintendent in Harrold, Texas, is seen in 2008. Troubled by school shootings around the country, Thweatt decided to arm school staff. Tony Gutierrez/AP hide caption

itoggle caption Tony Gutierrez/AP

Iowa Gov. Terry Branstad (left), Indiana Gov.-Elect Mike Pence (center) and Virginia Gov. Bob McDonnell, chairman of the Republican Governors Association, participate in a panel discussion during the 2012 RGA Annual Conference on Thursday in Las Vegas. Ronda Churchill/AP hide caption

itoggle caption Ronda Churchill/AP