Rep. Rick Crawford, R-Ark.National Journal

Heritage Action Fund is using a round of radio ads to attack three Republicans and a Democrat in agriculture-heavy districts over the farm bill, a spokesman said.

The advertisements, complete with squealing pig sound effects, hit Reps. Rick Crawford, R-Ark., Martha Roby, R-Ala., Frank Lucas, R-Okla., and Mike McIntyre, D-N.C., for pushing what Heritage calls a "food-stamp bill" through Congress.

The members are "putting a tuxedo on a pig" by backing the bill, the ads say. Heritage Action will spend a total of $50,000 across the four districts; the ads begin running today, according to Heritage Action spokesman Dan Holler.

This isn't the first time this cycle the Right has targeted Crawford, Roby, and Lucas. Earlier this year, the Club for Growth launched a website to seek primary challengers for each seat.

Crawford has been hit particularly hard. In March, Republicans criticized him for proposing a tax hike on millionaires. At the time, Grover Norquist accused Crawford of breaking the Americans for Tax Reform pledge and making a strategic "mistake." Crawford has also already been targeted by the Democratic Congressional Campaign Committee, which has hit him with a series of web and radio ads during the past several months. A DCCC spokesman declined to comment on whether Democrats will actually contest the seat, but given the district's GOP-tilt, turning it blue would be an uphill climb.

McIntyre, meanwhile, is at the top of Republicans' list of targets for the 2014 cycle. He was named to the National Republican Congressional Committee's "Red Zone" program earlier this month, which targets seven Democrats the party views as most vulnerable. Not only did Romney win McIntyre's district last year, but John McCain and George W. Bush carried it as well. McIntyre won by just 654 votes against Republican David Rouzer, who is already gearing up for another challenge.

So far, no Republican challengers have filed to take on Crawford, Lucas, or Roby in 2014.

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