“I was the owner of an entity which was a management entity,” Mr. Romney said on CBS, calling the questions about Bain the “height of silliness” to be having. “That entity was one which I had ownership of until the time of the retirement program was put in place. But I had no responsibility whatsoever after February of ’99 for the management or ownership — management, rather, of Bain Capital.”

Though he hit back hard at the president on Friday, Mr. Romney’s willingness to plunge fully into the fray over the issue was a victory for Mr. Obama in the sense that the campaign spent another day being fought on the Obama campaign’s choice of turf. As Mr. Romney himself said in an interview this week on Fox News, “If you’re responding, you’re losing.”

Mr. Romney used the television interviews on Friday to try to shift attention back to the economy.

“You just had very bad news on the economic front, with now 41 straight months with unemployment above 8 percent,” he told Fox News. “And what does the president do? He says he is going to raise taxes on people. He is trying to gut welfare reform as we know it. And he launches attacks of this nature. Well, it is just beneath the dignity of his office.”

But with the Obama forces apparently fully committed to portraying him as out of touch with the middle class and secretive about his wealth, Mr. Romney faced continuing questions about his willingness to disclose more information about his personal finances. He responded that he does not intend to disclose much more than he already has.

Mr. Romney said he had released his 2010 tax return and would release his full 2011 tax return when it was ready. But he said voters should not expect any more than that, despite Democrats’ calls for him to release a decade’s worth of returns or more, citing the example of his father, George Romney, who when he ran for the Republican presidential nomination in 1968 released 12 years of returns.

“I know there will always be calls for more. People always want to get more,” Mr. Romney said on CNN. “And, you know, we’re putting out what is required plus more that is not required. And those are the two years that people are going to have. And that’s — that’s all that’s necessary for people to understand something about my finances.”