President Obama's re-election campaign is attacking Mitt Romney's business experience, perhaps his strongest selling point as a candidate, in a new TV ad in five swing states. The presumptive Republican presidential nominee's campaign responds that it "welcomes" the "pivot back to jobs."

Private equity firms are under the microscope this week as a pro-Gingrich superPAC hounds GOP candidate Mitt Romney for his role as head of Bain Capital. Weekends on All Things Considered host Guy Raz talks with Dan Primack, senior editor of Fortune Magazine, about how these firms operate and the legitimacy of these attacks.

Mitt Romney's campaign has a new TV ad meant to counter attacks on his career at private-equity firm Bain Capital, using the same defense it has ever since his rivals for the front-runner for the Republican presidential nomination started taking populist jabs at him.

When a presidential candidate has a perceived political vulnerability, count on his intraparty rivals to go after it hard, even if they wind up eventually helping the efforts of the opposition party's White House candidate. That's essentially what we're seeing as Mitt Romney's fellow GOP presidential candidates attack him for presiding over layoffs as CEO of a private equity firm.