Unbowed by the backlash sparked by its last ad, the Obama-allied super PAC Priorities USA Action is up with yet another spot, again focusing attention on Mitt Romney's tenure at Bain Capital.

Unlike the previous ad, which tied Bain's closure of the GST Steel factory to the death of a worker's wife six years later, this spot steers clear of such explosive insinuations. But it does have similar attributes, including a GST worker describing Romney as a heartless capitalist.

That plant was my life, I mean, my livelihood… It fed me as a kid and fed my whole family as an adult. I depended on that plant, and I felt like it depended on me. Romney and Bain, they were businessmen, they had no idea how to make steel. They knew how to make money. They used us just like we were the scrap steel that we melted, you know, we were just a means to an end.

There is no word yet as to how much money Priorities USA Action is putting behind the spot, though co-founder Bill Burton noted in a press release that it is part of a "$20 million television and online project to educate voters about Mitt Romney’s business record and their impact on middle class families."

Romney's campaign has insisted that he was not responsible for GST Steel's closure, noting that the steel market was in crisis at the time and that Romney had already left Bain by the time the factory shut down.

UPDATE: 8:30 p.m. -- A Romney campaign spokesman responded to the ad in the following statement:

Just days after the President’s Super PAC released a heinous and despicable ad, and the Obama campaign was caught lying about it, the President’s allies have again come out with another discredited attack. After 42 months of unemployment above eight percent, it is clear that the President and his allies don’t have any rationale for reelection. We tried it President Obama’s way and the middle class has paid the price. Mitt Romney has a Plan for a Stronger Middle Class that will jumpstart the economy and bring back millions of jobs.
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  • Ed Conard

    Ed Conard of Mitt Romney's private equity firm Bain Capital is one of 12 donors who've given at least $1 million to the super PAC Restore Our Future, which supports Romney's bid for the White House. Due to the obliteration of campaign finance law by the Supreme Court, donors can give unlimited amounts to the super PAC. Meet Romney's dozen.

  • Blake Roney

    Blake Roney, Nu Skin (Personal Care Products). Gave $1 million as part of a shell corporation.

  • Steven Lund

    Steven Lund, Nu Skin. Gave $1 million as part of a shell corporation.

  • Robert Mercer

    Robert Mercer, left, Renaissance Technologies (Financial)

  • John Paulson

    John Paulson, Paulson & Co. (Financial)

  • Julian Robertson

    Julian Robertson, Tiger Management (Hedge Fund)

  • Paul Singer

    Paul Singer, right, of Elliot Management (Hedge Fund)

  • Melaleuca

    Melaleuca and owner Frank VanderSloot (Personal Care)

  • Paul & Sandra Edgerley

    Paul & Sandra Edgerley, Bain Capital

  • Bob Perry

    Bob Perry, Perry Homes (Home Builder)

  • Francis Rooney

    Francis Rooney, Rooney Holdings (Financial)

  • Oxbow Corp. and William Koch

    Oxbow Corp. and owner William Koch (Energy & Technology)