WASHINGTON — Senator McCain, responding to the crisis on Wall Street, is calling for a financial commission modeled on the panel that investigated the terrorist attacks of September 11, 2001, a move that Senator Obama is deriding as a “stunt.”

The two presidential candidates traded shots yesterday as they vied for the high ground on the economy, which sprang to the fore of the campaign amid the fallout from the collapse of the storied investment bank Lehman Brothers.

Mr. McCain, in an appearance on CBS’s “The Early Show,” called for a probe of the financial sector and criticized the “greed” and “corruption” of Wall Street executives.

“We need to set up a 9/11 Commission in order to get to the bottom of this and get it fixed and act to clean up this corruption,” he said. In a later economic speech in Orlando, he did not elaborate on the proposed panel, but he pledged reforms “to put an end to the reckless conduct, corruption, and unbridled greed that have caused a crisis on Wall Street.”

Mr. Obama, in his own speech in Colorado on the Wall Street woes, pounced on Mr. McCain’s suggestion. “Instead of offering up concrete plans to solve these issues, Senator McCain offered up the oldest Washington stunt in the book — you pass the buck to a commission to study the problem,” Mr. Obama said. “But here’s the thing — this isn’t 9/11. We know how we got into this mess. What we need now is leadership that gets us out. I’ll provide it, John McCain won’t, and that’s the choice for the American people in this election.”

The Democratic nominee characterized the current crisis as “nothing less than the final verdict on an economic philosophy that has completely failed,” placing blame squarely on Bush administration policies that he said Mr. McCain was running to continue. While offering no new proposals, the Illinois senator outlined a series of plans he has previously put forward, including an overhaul of the financial regulatory structure and a crackdown on market manipulation.

The proposals also included Mr. Obama’s own version of a new high-level commission, a “standing financial market advisory group” that he said would meet regularly and advise the president, Congress, and regulators on risks to the financial markets.

A spokesman for the Republican National Committee, Alex Conant, noted that Mr. Obama “has supported creating several commissions and applauded their results during his short political career.”

He said the Democrat was “putting politics first.” “In typical Washington fashion, Obama would rather attack John McCain than welcome a good bipartisan idea,” Mr. Conant said.

After Mr. Obama’s speech, his campaign convened a conference call with a former Treasury secretary in the Clinton administration, Lawrence Summers, and a former chairman of the Securities and Exchange Commission appointed by President Bush, William Donaldson. The two praised the Illinois senator’s plans and criticized both the Bush administration and Mr. McCain for reacting slowly to the crisis.

Both Mr. Summers and Mr. Donaldson, however, have current ties to the financial industry as executives in investment firms. Though lawmakers from both parties have faulted the broader regulatory system for the Wall Street predicament, some have blamed the plunging values of Lehman, Merrill Lynch, and Fannie Mae and Freddie Mac on hedge fund investors who make money by short selling shares of the firm’s stock.

Mr. Donaldson serves as chairman of his own investment firm, Donaldson Enterprises, and on an advisory board of Perella Weinberg Partners, a boutique investment bank. He said in a phone interview that he was neither involved in or aware of Perella’s investment activities. As for Donaldson Enterprises, he said: “Neither I nor my firm has engaged in short-selling.”

Mr. Summers is a managing director at D.E. Shaw, a New York-based hedge fund. A spokeswoman for the firm, Darcy Bradbury, said Mr. Summers was not a “stock picker.”

“We on any given day are long and short literally thousands of different stocks, just like every other major financial firm on Wall Street,” she said. “He’s not involved in picking individual stocks.”