For the past two weeks, John McCain's Trash Talk Express has rolled over Barack Obama, flattening the Illinois senator's lead in many national polls and directing public attention away from the fundamental political choices the nation has to make and toward Obama's allegedly elitist character.

Campaigning against Democrats' allegedly elitist characters has been the Republican formula for presidential victory for the past 20 years, ever since uber-consultant Lee Atwater realized he could steer the populist sentiments of many voters against cultural rather than economic elites. The Atwater ploy often requires GOP consultants to manufacture evidence of the Democratic candidate's cultural marginality, but over the past fortnight, McCain's campaign, with its nose dive into Paris Hilton Plays the Race Card thematics, has proved equal to the task.

Which leaves Barack Obama with a problem: How to move the election back to a referendum on the direction of our economic and security policies, while also reassuring swing voters that he's not the "presumptuous" (this year's Republican code word for "uppity") novice, disconnected from the travails of ordinary Americans, that McCain makes him out to be.

The way to accomplish almost all these tasks would be for Obama to become a more convincing tribune for working- and middle-class Americans. It was one thing for Obama to lose the white working-class vote to Hillary Clinton, whose fundamental economic policies weren't all that different from his own. But to have as much trouble with that constituency against John McCain, even allowing for the reluctance of many white Americans to make a black man president, bespeaks Obama's ongoing difficulty in persuading voters that he's on their side in matters economic and that John McCain isn't.

One key contrast Obama has been reluctant to draw is over globalization and investment. On these issues (and most others), McCain is a standard-issue Republican. He's never met a trade deal he didn't like, and his formula for boosting the American economy is to preserve tax cuts for the very rich and slash taxes on corporations. Obama, by contrast, acknowledges the costs as well as the benefits of trade and argues that globalization requires strengthening the safety net for American workers at home and putting enforceable labor standards into any future trade deals. Unlike McCain, he favors a domestic investment policy that designates tax dollars and tax credits for building a greener economy.

But these are contrasts that Obama has yet to draw in a compelling way. In a speech on the economy Friday in St. Petersburg, Fla., he talked about investing in infrastructure projects and green jobs without contrasting his stances with those of McCain, or of George W. Bush, whose economic policies are essentially indistinguishable from McCain's.

Essentially, Obama is declining to swing at hanging curve balls. That's not a strategy for victory.

What's wrong with going after McCain's proposal for across-the-board corporate tax cuts? McCain would reward corporations that move their factories from the Midwest to the Middle Kingdom. In the first three months of this year, fully 35 percent of the profits of American companies came from their overseas operations. As The New York Times's Floyd Norris has pointed out, that's almost twice the percentage of profits that U.S. business derived from abroad just a decade ago. But McCain's proposal would cut taxes on a company that kept its headquarters here and had all its production, and virtually all its employees, in China or India or Vietnam.

Obama's tax proposals offer no such rewards for offshoring American industry. And his investment policies — which call for spending $150 billion over the next decade on building a more energy-efficient economy, and offering $4 billion to the domestic auto industry to build more energy-efficient autos — employ public funds to boost the U.S. economy in a period when private funds are used to boost the economies of other nations.

But Obama could do more to boost the domestic economy. Ralph Gomory, former president of the Sloan Foundation (and before that, the chief of research at IBM), makes the case that our tax code should reward corporations for creating decent-paying, high-value-added jobs here at home. Gomory's "onshoring" strategy is one of the few economic proposals that would actually begin to level the global playing field. As such, it is one Obama should consider embracing.

McCain rewards investment abroad; Obama rewards investment at home. McCain offshores; Obama onshores. Some of Obama's more Wall Street-oriented advisers may be uncomfortable with these themes and policies, but Obama isn't running for president of Wall Street. If he can remember that, the election is still his to lose.

Meyerson is editor-at-large of American Prospect and the L.A. Weekly. He wrote this commentary for The Washington Post.

Essentially, Obama is declining to swing at hanging curve balls. That's not a strategy for victory.