(FORTUNE Magazine) – In early September the Republican leadership in Congress met with President Bush in the West Wing's stately Cabinet Room. They delivered bad news: Voters who once supported him overwhelmingly were beginning to abandon him. Bush's missteps in Iraq and his failure to create more jobs, they said, have made him particularly unpopular in three pivotal states--Illinois, Michigan, and Ohio. Sensing the President's vulnerability, Democrats have blown open their race to replace him. During the summer, polls showed former Vermont governor Howard Dean with a clear lead in the early primary and caucus states. But by the end of September a national survey by USA Today, CNN, and Gallup had retired Army General Wesley Clark in the lead, and three other candidates running neck-and-neck with Dean. In a contest against Bush, the poll showed, Clark and Massachusetts Senator John Kerry would narrowly prevail.

Election 2004, which has for months looked like a slam-dunk for Bush, is now a jump ball. Any of the top Democratic candidates has a shot at beating him. As a result, Democratic voters are holding their wannabes to a higher standard. "Democrats want to choose a candidate who can win, not just inflame their partisan spirits," says pollster John Zogby. "They want to find someone who can attract enough independent voters to be electable against George Bush."

No one is working harder to meet that standard than Dean, who continues to be the front-runner. The latest polls at presstime in Iowa and New Hampshire put him five to ten percentage points ahead of his closest opponents. Dean still tosses rhetorical red meat to his large, anti-Bush crowds. But he also highlights his conservative credentials, such as his opposition to federal gun-control laws and his preference for balanced budgets. "We think he's in the center," Dean's campaign manager, Joe Trippi, says.

That contention will be hard to prove. Vermont state taxes are among the highest in the nation. In fiscal 2001 (the last year available) it ranked third in tax collections per $1,000 of its citizens' income--behind Hawaii and New Mexico--according to the nonpartisan Tax Foundation. And although Dean didn't increase the state's personal income tax during his 11 years as governor, he raised taxes on almost everything else, including gasoline, cigarettes, beer, telephones, hotel rooms, property, and corporate income. In 2002 the libertarian Cato Institute, which is a good judge of fiscal conservatism, gave Dean a "D" for his overall revenue and spending policies.

Clark, in contrast, is a blank slate. As a neophyte politician, he has no domestic policy record, and a top aide admits that his positions are still "fluid." But the more concrete Clark becomes on the issues, the more likely he is to alienate some of the people who now say they support him. Few pollsters believe that Clark can sustain the level of popularity he registered after he entered the race in September.

Bush's low ratings could well be temporary. Most experts believe the economy will improve over the next year, and it's hard to imagine the situation in Iraq getting much worse. Presidents Reagan and Clinton both trailed in the polls at this point in their first terms, yet went on to score impressive victories. As we well know, a year is an eternity in politics. --Jeffrey H. Birnbaum