Bill Clinton endorsed Rep. Mark Critz in the Democratic primary race for Pennsylvania's 12th district seat in the U.S. House of Representatives.

Critz was elected to Congress in a special election against Republican Tim Burns in 2010 for the post previously held by the late Rep. John Murtha. Critz, who was a longtime aide to the Pennsylvania Democrat, is running against Rep. Jason Altmire (D-Pa.) in the April 24 contest. The Pittsburgh Post-Gazette reports:

Mr. Altmire, 44, and Mr. Critz, 50, were locked into the April 24 primary by Republican mapmakers tasked with eliminating one of Pennsylvania's 19 congressional districts after the 2010 U.S. Census. They combined their two current districts into one covering parts of parts of Allegheny, Beaver, Cambria, Lawrence, Somerset and Westmoreland counties. Edgeworth attorney Keith Rothfus is unopposed for the GOP nomination to the seat.

"I am proud to endorse Mark Critz for Congress," Clinton said in a statement. "I know that Mark will continue his work to create jobs, strengthen the middle class, to protect Social Security and Medicare, and do what is right for western Pennsylvania and our nation."

Critz touts Clinton's support in a new campaign ad.

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