Updated

Very infrequently does the National Rifle Association get in the middle of a Democratic primary contest.

However, the group thinks it has a winning issue in Pennsylvania, where Philadelphia's former mayor is vying for the Democratic gubernatorial nomination against the state's auditor general and the son of a former governor.

The NRA, seizing on Pennsylvania's rural, conservative sensibilities has run a series of ads criticizing Ed Rendell, who served as Philadelphia mayor for nine years before leaving to join the Democratic National Committee as its general chair and 2000 chief election organizer. The NRA is chasing Rendell, the frontrunner in the Democratic race, for his strident, longtime position on gun control.

"My opponent was for gun control, and is today," Robert Casey Jr., Rendell's opponent, said on the campaign trail. "I just want to enforce the existing laws."

"The NRA ads are just like the Casey ads. They don't tell the truth. There is nothing I want to do to take a gun away from a hunter or a law-abiding citizen," Rendell countered.

Rendell does support a one-gun-per-month law, but exempts rifles and shotguns, collectors and gun dealers. Still, he may find any gun control issues a tough sell outside Philadelphia.

That's because the NRA has 2 million members in Pennsylvania, second only to California in statewide memberships. Counties with names like Elk, Erie, Susquehanna, and Beaver are rampant hunting areas for the more than half-million deer in the state, not to mention turkey and other game.

By jumping into the fray, the NRA is accomplishing two objectives — broadening its constituency and targeting Democrats whose gun values the NRA wants to leave on the rack.

"You've got the working man, the union member, the guy who works in the mine and then goes hunting on the weekend. Historically they are aligned with the Democratic Party but culturally they are conservative. They embrace the values of the NRA," said Chuck Wild, an NRA activist.

If the ad campaign is successful, the gun lobby vows to take aim at other races coming this fall.

"In states like West Virginia, where you have a lot of sportsmen and a lot of hunters, people might otherwise vote Democratic, but because of the issue or the perception that Dems are anti-gun, some people will swing the other way," said political journalist Bill Sammon.

"I think it's changing the politics of Democratic policies. I think it's making Dems rethink this whole idea that they have to take a knee-jerk anti-gun response to every issue," Wild said.

Voter turnout will be the key to the NRA's success or failure. Rendell has been leading in the most recent Mason-Dixon poll, 48-41 with 11 percent undecided.

But Casey is running strong in many rural, conservative districts where the NRA expects to find most of its support. If Casey wins, he will go up against Republican nominee and state Attorney General Mike Fisher, who is running unopposed. Fisher supports enforcing existing laws so a Fisher-Casey race will create a win-win race for the NRA.