However, in a dizzying day of speeches and statements, neither White House hopeful offered any fresh ideas for turning things around. Instead each relied on the same vague, though vastly different, pitches he has sounded over the past few months for fixing what ails the country.
And they didn't emphasize that they are part of the Congress that has done little to head off the crisis. McCain is a four-term Arizona senator, Obama a first-termer from Illinois.
Bemoaning "the most serious financial crisis since the Great Depression," Democrat Obama faulted Republican McCain's domestic policy agenda as the same as President Bush's - "one that says we should just stick our heads in the sand and ignore economic problems until they spiral into crises."
McCain declared in a new TV ad, "Our economy is in crisis. Only proven reformers John McCain and Sarah Palin can fix it" - though he also told voters in Jacksonville, Fla., "The fundamentals of our economy are strong."
While presidents - and candidates of the party occupying the White House - often take credit for good economies and try to avoid blame for bad ones, financial crises nearly always have multiple causes.
Home loans became more affordable a few years ago when the Federal Reserve kept interest rates low. Politicians of all stripes encouraged home ownership. But lightly regulated financial outfits began slicing and dicing the resulting mortgages into securities and selling them to investors.
Eventually, it all began collapsing, prices dropped, people started losing their homes and Wall Street went into a spin.
This is the backdrop with some seven weeks left in the campaign, and both Obama and McCain are trying to find a message that resonates with anxious voters who are fretting about their retirement nest eggs, home mortgages and job security.
As different as their policies are, they were united in their message to voters: It's not your fault.
Courting working class voters who gave him grief in the Democratic primary, Obama sounded an I-feel-your-pain note.
Obama lamented Republican policies over eight years that he said "encouraged outsized bonuses to CEOs while ignoring middle-class Americans" and said: "Instead of prosperity trickling down, the pain has trickled up - from the struggles of hardworking Americans on Main Street to the largest firms of Wall Street."
McCain's words were sympathetic as well.
"America is in a crisis today," he said - then added: "The economic crisis is not the fault of the American people. Our workers are the most innovative, the hardest working, the best skilled, the most productive, the most competitive in the world.
... But they are being threatened today ... because of greed and corruption that some engaged in on Wall Street and we have got to fix it."
Some in the markets, he said, "have treated Wall Street like a casino."
The upheaval at Lehman Brothers Holdings Inc., Merrill Lynch & Co., and American International Group Inc. - and the stunning reordering of the financial market that has following - gave the candidates an opening to press their economic ideas anew.
In line with historical positions of Democrats and Republicans, Obama generally supports stronger consumer protections, better regulatory oversight and more government intervention, while McCain broadly prefers a market system of less federal involvement and red tape.
Both advocate tax cuts, though to different degrees and different ends. Obama seeks to cut into inequality between rich and poor by raising taxes on the wealthiest Americans and give breaks to the middle class and lower-income people. McCain wants to spur the economy and create jobs by keeping tax rates low for higher-income taxpayers and slashing rates for corporations.
While they focused on the topic that voters say matters most, the two campaigns also continued to assail each other Monday on character issues. The Democratic vice presidential nominee, Joe Biden, said McCain was "launching a low blow a day." McCain's campaign, in turn, accused Obama of spouting "false talk about change" and hurling insults to cover up his record.
Yet, even that increasingly personal griping took a back seat as Obama and McCain maneuvered for an edge on the economy with stocks tumbling as investors reacted to the latest Wall Street turmoil.
Obama has led for months on the question of who would best handle the economy, but some polls show that his advantage has dwindled. He had a slight advantage over McCain on the economy - 47 percent to 42 percent - in an ABC News/Washington Post poll last week, the Democrat's edge cut in half since spring. However, CNN's latest poll showed Obama with a larger edge, 52 percent to 44 percent, with no movement from early this year.
McCain focused mostly on a need for regulatory reforms and applauded the federal government's refusal to bail out the latest cash-strapped institutions. It was a posture designed to bolster his free-market stance and strike a populist chord.
He promised: "The McCain-Palin administration will replace an outdated, patchwork quilt of regulatory oversight and bring transparency and accountability to Wall Street. We will have transparency and accountability and we will reform the regulatory bodies of government." He didn't say precisely how.
At a campaign appearance in Grand Junction, Colo., Obama chastised McCain by saying: "It's not that I think John McCain doesn't care what's going on in the lives of most Americans. I just think he doesn't know. He doesn't get what's happening between the mountains in Sedona where he lives and the corridors of power where he works."
As for government regulation, he said, "For years I have called for modernizing the rules of the road."
It's been nearly a decade since Congress and President Clinton reshaped the financial landscape. That 1999 legislation removed Depression-era barriers between commercial banks and investment firms and allowed the creation of financial behemoths where years later the risks of underwriting subprime mortgages were somewhat hidden.
Former Sen. Phil Gramm, R-Texas, until recently one of the McCain campaign's top economic advisers, was a chief writer of that law.
McCain voted for a Senate version of the bill but did not vote on the final package. Biden voted against the Senate legislation but for the final compromise that Clinton signed. Obama was not in Congress at the time.
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