CHARLESTON, W.Va. (AP) — After years of showering U.S. Sen. Joe Manchin with stellar ratings and campaign endorsements, the National Rifle Association targeted the West Virginia Democrat with a TV ad launched Wednesday over his continuing push for broader gun buyer background checks.

The new ad urges viewers to phone Manchin’s office and tell him “to honor his commitment to the 2nd Amendment.” It alleges Manchin “is working” with President Barack Obama, who is deeply unpopular in West Virginia, and New York Mayor Michael Bloomberg, a vocal advocate of gun control laws.

Manchin has co-sponsored a background check measure with Sen. Patrick Toomey, R-Pa. It would apply to buyers in commercial settings such as gun shows and online but exempt non-commercial transactions such as sales between friends and relatives. It failed to advance on an April vote, but Manchin has since sought additional support for the measure while remaining open to revising its provisions to ease concerns of gun rights’ backers.

Manchin said the NRA is not being honest about his proposal.

“Unfortunately, the NRA leadership in Washington has lost its way and is more concerned about political power than gun rights and gun safety,” Manchin said in a statement. “I am the same proud gun owner and NRA member that I have always been and I believe that criminal and mental background checks are a commonsense approach to protect our neighbors and children without infringing on our 2nd Amendment rights. I think most NRA members agree with me.”

The NRA plans to spend $100,000 airing it in West Virginia markets over the next two weeks, spokeswoman Jacqueline Otto said in a statement.

The killing of 20 first-graders and six adults at Sandy Hook Elementary School in Newtown, Conn., by a gunman six months ago this Friday helped spur Manchin’s legislation. Representing a state where gun ownership and hunting are long-held traditions, Manchin has said he believes he can credibly provide reasonable proposals to the resulting debate.

The NRA ad contrasts Manchin’s proposal with a TV spot from his 2010 Senate campaign. Called “Dead Aim,” it shows Manchin loading a rifle as he touts his NRA backing and support of the Second Amendment. He then shoots environmental legislation sought by the Obama administration. Manchin won that special election to complete the term of the late Robert C. Byrd and was elected to a full 6-year term in 2012.

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