Big events have big impacts. The financial crisis is a big event. The presidential campaign -- not so much. This election is being driven more by events than by the campaign. The debates, for example, have not had much impact. Certainly not nearly as much as the stock market crash.

Nearly six in 10 Americans say they think that the country is headed for a depression like the one in the 1930s "in which roughly one in four workers were unemployed, banks failed across the country, and millions of ordinary Americans were temporarily homeless or unable to feed their families." That description was given in a CNN poll this month conducted by Opinion Research. Fifty-nine percent of voters think that a similar depression is somewhat or very likely.

And for the first time, Barack Obama had a statistically significant lead -- 8 points -- over John McCain in the poll. The two sentiments are closely connected. Seventy-five percent of the people who think that a depression is "very likely" are voting for Obama. "Somewhat likely"? Sixty-five percent for Obama. "Not very likely?" A close split. Those who believe that another depression is "not likely at all": 63 percent for McCain.

McCain is offering his prescription. "A vote for me will guarantee immediate pro-growth action," he promised in Columbus, Ohio. "Tax cuts for hardworking families, support for small businesses... and an end to pork-barrel, corrupting spending in Washington." But more and more voters think that McCain's policies would be the same as those of President Bush (56 percent now, up from 50 percent after the Republican convention). Bush's job-approval rating, 24 percent, is as low as President Nixon's was just before he resigned.

Only 26 percent of Americans have confidence in Bush's ability to handle the nation's financial crisis. Faith in McCain's ability to do so is higher (50 percent). But more than two-thirds (68 percent) have confidence in Obama's ability to deal with the problem. The Democrat said in Virginia, "The rescue package we just passed in Congress isn't the end of what we need to do to fix the economy. It's the beginning of what we need to fix our economy.'"

Why do voters have confidence in Obama's economic skills? Partly because he has a lot of President Clinton's people around him. "We need to do what a guy named Bill Clinton did in the 1990s and put people first again," Obama said in Pennsylvania.

The bad economy is driving a growing consensus that Obama is going to win. In the CNN poll, 61 percent of Americans said they think that the Democratic nominee will be elected. That's greater than the number who are voting for him (53 percent). Nearly one-third of Republicans think that their nominee is going to lose.

Still, Obama supporters worry about the "Bradley effect," white voters telling pollsters they intend to vote for an African-American candidate but then not doing so. In the 1982 California gubernatorial election, a black candidate, Tom Bradley, was ahead in the pre-election polls and ended up losing to a white candidate. The effect also may have played a part in Sen. Jesse Helms's victory over a black candidate in North Carolina in 1990, and in the unexpectedly close triumphs of two African-American candidates in 1989, Douglas Wilder for governor of Virginia and David Dinkins for mayor of New York City.

But the impact seems to be getting smaller. David Bositis of the Joint Center for Political and Economic Studies notes that in 2006, the Bradley effect did not seem to hinder black politicians running in major statewide races. Pre-election polls accurately predicted the outcomes -- with whites voting the way they said they would.

Obama's supporters should worry more about something else: the number of unsure voters. Specifically, is that number greater than Obama's lead? Take Florida, where an average of three recent polls shows Obama leading McCain by 3 points (49 percent to 46 percent). Five percent of Florida voters say they are still undecided. Very few black voters are unsure. If the unsure voters end up going for McCain, he would overtake the Democrat's narrow lead in Florida. Obama supporters cannot feel comfortable unless their candidate's lead is larger than the number of unsure voters.

This article appeared in the Saturday, October 18, 2008 edition of National Journal.

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