John McCain's meandering campaign may have finally found its footing. After a week spent peddling overblown charges that Barack Obama snubbed troops in Germany and touting the virtues of sunscreen, the Republican launched a TV ad Wednesday that targets his rival's biggest weakness: his status as a global rock star.

It is, of course, the single biggest factor that propelled Obama's rise from neophyte to nominee. One by one, Democratic rivals quit the primary race, grumbling about how hard it was to draw the spotlight away from Obamamania. But today -- after a globetrotting tour that played out exactly as aides had hoped, and that's the problem -- that same cult of celebrity jeopardizes a candidate who needs to offer up an unusually large amount of one of the rarest commodities in politics: modesty.

His lack thereof appeared to be on display Tuesday evening on Capitol Hill. "This is the moment... that the world is waiting for," Obama told House Democrats, according to the Washington Post. "I have become a symbol of the possibility of America returning to our best traditions."

Folks don't run for president unless they think they're pretty hot stuff.

Did somebody say, "Yes, I Can"?

(Not exactly, we're told. House Democrats responded to the Post's report of the closed-door meeting with a fuller context of Obama's quote, which they said was preceded by this: "The campaign... is not about me at all. It's about America. I have just become a symbol.")

Obama, of course, is behaving no differently than any other presidential candidate, all of whom must project strong, tough-minded confidence that can be easily interpreted as arrogance. Folks don't run for president unless they think they're pretty hot stuff.

But there is a darker subtext at play here: The world is watching this campaign with the expectation that racism will eventually play a clear role in its outcome. But what we're seeing play out today, this heightened focus on Obama's "arrogance" or "audacity," is a subtle, but powerful, form of racist thinking: that an African American, no matter how successful, must always remain humble. As he does in so many other ways, Obama faces a different threshold for behavior that will be deemed acceptable by many voters.

There's one other thing Obama should guard against: complacency.

"We are now in a position," he said Monday night in Arlington, Va., a full 99 days before Election Day, "where the odds of us winning are very good."

That sounds like something another Democrat would have said late last year, with fewer than 99 days to go before the Iowa caucus. Her name? Hillary Rodham Clinton.

One of the most enduring images of the 1988 campaign was Michael Dukakis mowing his lawn in the summer before the Democratic convention, on a day when the Lee Atwater-inspired campaign of George H.W. Bush was preparing to launch a merciless series of attacks against him. After Dukakis lost 40 states that fall, Democrats waved around that photograph and pilloried him for having been overly confident. But at the time, you might forgiven him that indulgence. Going into his convention, he led Bush by 18 points.

Obama vs. McCain is a dead heat.