In the 12 days between the first presidential debate Sept. 26 in Oxford, Miss., and the second debate Tuesday in Nashville, Tenn., the United States took a 6.0 hit on the economic Richter scale. That fact changed not only the emphasis of the second meeting but also its political dynamics.

Twelve days ago, Republican John McCain had narrowed the gap between his campaign and that of Democrat Barack Obama. But his over-the-top and ineffectual reaction to the crisis on Wall Street created doubts in the minds of an increasing number of undecided voters. As a result, Obama has begun to pull away in the polls, particularly in voters' assessment of which candidate is better equipped to deal with the economy.

So McCain had to prove his economic chops Tuesday in Nashville, to come off as a combination of Franklin Roosevelt and investment guru Warren Buffett, a tough assignment for a conservative Republican — particularly in that, as McCain noted, Buffett supports Obama.

McCain was better on the economy last night, but not good enough to calm the doubts created by his 26-year record in Congress, his reputation as an opponent of government regulation and surely not good enough to overcome his inconsistent responses to the financial crisis.

His big surprise was to suggest that the government step in right away and take over troubled home mortgages. That option is contained in the $700 billion rescue plan signed into law Friday by President George W. Bush. But McCain would take the option out of it. "As president, I would order the Treasury secretary to buy up the bad home loan mortgages," he said.

Alas, his first response to the questions about the economy that dominated the first hour of the 90-minute debate was to fall back to his standard talking points: energy independence, low taxes and cutting government spending. As a cure for his ailing campaign, that wasn't exactly pulling a rabbit from a hat.

McCain stressed his credentials as a reformer — but strangely, the word "maverick" hardly was heard. But he missed an opportunity, when asked by a audience member in the "town hall" format what kind of sacrifice he would demand from Americans, to point out his excellent record of support for national service. Instead, he said he would cut bureaucracy and earmarks.

Obama didn't hit that one out of the park, either, talking about fuel-efficient cars and cutting down home energy use. Indeed, at a time of economic crisis, Americans may wonder why neither candidate was willing to inspire or challenge them.

For his part, Obama played it cautious, returning time and again to his plan to cut taxes for the middle class — the now-familiar "95 percent of working Americans."

He scored his biggest point of the night in response to a question from moderator Tom Brokaw of NBC about whether health care was a "privilege a responsibility or a right."

"Well, I think it should be a right for every American," he said. "In a country as wealthy as ours, for us to have people who are going bankrupt because they can't pay their medical bills — for my mother to die of cancer at the age of 53 and have to spend the last months of her life in the hospital room arguing with insurance companies because they're saying that this may be a pre-existing condition and they don't have to pay her treatment, there's something fundamentally wrong about that."

McCain's response that health care was a "responsibility" because "government mandates make me a little nervous" suggested that he may be out of touch with the realities of the middle class, as well as disconnected from the realities of contemporary American health care.

He'll have one more chance, in the third and final debate next Wednesday, to prove he's in touch. By then it could be too late. In Nashville, of all places, it wasn't that he didn't know the words to the song, but that he couldn't hear the music.

REPRINTED FROM THE ST. LOUIS POST-DISPATCH.